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The Role of Flight Tests and ofFlight Simulationin Aircraft Design
Fabrizio Nicolosi Agostino De Marco⁽⁾ Pierluigi Della Vecchia
University of Naples ldquoFederico IIrdquowwwuninait
Department of Aerospace Engineering (DIAS)wwwdiasuninait
Aircraft Design amp Aeroflightdynamics Group (ADAG)wwwdiasuninaitadag
⁽⁾agostinodemarcouninait
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Layout of the presentation
bull A case study the Tecnam P2006T aircraft Flight test instrumentation Flight tests for certification Evaluation of stability and flight qualities Aircraft system identification (parameter estimation)
bull JSBSim an open source Flight Dynamics Model (FDM) software library
bull Desktop 6DoF simulations
bull Simulation-based aircraft design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
P2006T aircraft
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
CS-23FAR-23 Certified Cockpit
Baggagecompartment
P2006T aircraft
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
CS-23FAR-23 Certified
P2006T and other similar airplanes
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel tests
Scale Model (165)Fluorescent oil film visualizations
DIAS low-speed wind tunnelTest section 2 m times 14 m
Transitionstrips
Turbulence Intensitysim 01
Max speedsim 45 ms
Re asymp 06times106
In-FlightRe asymp 60times106
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Pitching moment coefficient measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different stabilator deflection angles δs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Lateral-directional coefficients measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different rudder deflection angles δr
Roll
Yaw
Side-force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
PitotProbe α - Flag
β - Flag
AHRSControl Unit (PC) GPS Antenna
Aileron Deflection PotentiometerSpaceAge Control Mini Air Data Boom
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Calibrations
COTS sensorΑngle α and β accuracy verified in wind tunnel 02 degUsed to calibrate aircraft pitotstatic system
Load cell calibration Then applied to the control stick
lsquoSpeed coursersquo technique evaluate CASCross check with differential GPS outputs
CAS vs IAS
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
AC Total Pressure Probe
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Stall tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Requirements CS 2349 and CS 23201
bull starting from a speed at least 10 kts above the stall speed bull longitudinal control must be pulled back bull rate of speed reduction will not exceed 1 knots (level stall) and 3 knotss (turning stall)
Tests have been performed in the following configurations and conditions
bull Maximum weight take offbull Engine running at 75 and idle bull Flap a 0⁰ 15⁰ and fullbull Landing gear retracted and extendedbull Trim speed ( = 15VS1)bull CG in the max forward and aft positionbull Turning stall with 30⁰ of bank
hellipleading to more than 100 stalls to accomplish certification requirements
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Layout of the presentation
bull A case study the Tecnam P2006T aircraft Flight test instrumentation Flight tests for certification Evaluation of stability and flight qualities Aircraft system identification (parameter estimation)
bull JSBSim an open source Flight Dynamics Model (FDM) software library
bull Desktop 6DoF simulations
bull Simulation-based aircraft design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
P2006T aircraft
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
CS-23FAR-23 Certified Cockpit
Baggagecompartment
P2006T aircraft
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
CS-23FAR-23 Certified
P2006T and other similar airplanes
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel tests
Scale Model (165)Fluorescent oil film visualizations
DIAS low-speed wind tunnelTest section 2 m times 14 m
Transitionstrips
Turbulence Intensitysim 01
Max speedsim 45 ms
Re asymp 06times106
In-FlightRe asymp 60times106
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Pitching moment coefficient measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different stabilator deflection angles δs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Lateral-directional coefficients measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different rudder deflection angles δr
Roll
Yaw
Side-force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
PitotProbe α - Flag
β - Flag
AHRSControl Unit (PC) GPS Antenna
Aileron Deflection PotentiometerSpaceAge Control Mini Air Data Boom
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Calibrations
COTS sensorΑngle α and β accuracy verified in wind tunnel 02 degUsed to calibrate aircraft pitotstatic system
Load cell calibration Then applied to the control stick
lsquoSpeed coursersquo technique evaluate CASCross check with differential GPS outputs
CAS vs IAS
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
AC Total Pressure Probe
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Stall tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Requirements CS 2349 and CS 23201
bull starting from a speed at least 10 kts above the stall speed bull longitudinal control must be pulled back bull rate of speed reduction will not exceed 1 knots (level stall) and 3 knotss (turning stall)
Tests have been performed in the following configurations and conditions
bull Maximum weight take offbull Engine running at 75 and idle bull Flap a 0⁰ 15⁰ and fullbull Landing gear retracted and extendedbull Trim speed ( = 15VS1)bull CG in the max forward and aft positionbull Turning stall with 30⁰ of bank
hellipleading to more than 100 stalls to accomplish certification requirements
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
P2006T aircraft
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
CS-23FAR-23 Certified Cockpit
Baggagecompartment
P2006T aircraft
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
CS-23FAR-23 Certified
P2006T and other similar airplanes
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel tests
Scale Model (165)Fluorescent oil film visualizations
DIAS low-speed wind tunnelTest section 2 m times 14 m
Transitionstrips
Turbulence Intensitysim 01
Max speedsim 45 ms
Re asymp 06times106
In-FlightRe asymp 60times106
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Pitching moment coefficient measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different stabilator deflection angles δs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Lateral-directional coefficients measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different rudder deflection angles δr
Roll
Yaw
Side-force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
PitotProbe α - Flag
β - Flag
AHRSControl Unit (PC) GPS Antenna
Aileron Deflection PotentiometerSpaceAge Control Mini Air Data Boom
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Calibrations
COTS sensorΑngle α and β accuracy verified in wind tunnel 02 degUsed to calibrate aircraft pitotstatic system
Load cell calibration Then applied to the control stick
lsquoSpeed coursersquo technique evaluate CASCross check with differential GPS outputs
CAS vs IAS
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
AC Total Pressure Probe
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Stall tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Requirements CS 2349 and CS 23201
bull starting from a speed at least 10 kts above the stall speed bull longitudinal control must be pulled back bull rate of speed reduction will not exceed 1 knots (level stall) and 3 knotss (turning stall)
Tests have been performed in the following configurations and conditions
bull Maximum weight take offbull Engine running at 75 and idle bull Flap a 0⁰ 15⁰ and fullbull Landing gear retracted and extendedbull Trim speed ( = 15VS1)bull CG in the max forward and aft positionbull Turning stall with 30⁰ of bank
hellipleading to more than 100 stalls to accomplish certification requirements
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
P2006T aircraft
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
CS-23FAR-23 Certified Cockpit
Baggagecompartment
P2006T aircraft
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
CS-23FAR-23 Certified
P2006T and other similar airplanes
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel tests
Scale Model (165)Fluorescent oil film visualizations
DIAS low-speed wind tunnelTest section 2 m times 14 m
Transitionstrips
Turbulence Intensitysim 01
Max speedsim 45 ms
Re asymp 06times106
In-FlightRe asymp 60times106
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Pitching moment coefficient measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different stabilator deflection angles δs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Lateral-directional coefficients measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different rudder deflection angles δr
Roll
Yaw
Side-force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
PitotProbe α - Flag
β - Flag
AHRSControl Unit (PC) GPS Antenna
Aileron Deflection PotentiometerSpaceAge Control Mini Air Data Boom
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Calibrations
COTS sensorΑngle α and β accuracy verified in wind tunnel 02 degUsed to calibrate aircraft pitotstatic system
Load cell calibration Then applied to the control stick
lsquoSpeed coursersquo technique evaluate CASCross check with differential GPS outputs
CAS vs IAS
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
AC Total Pressure Probe
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Stall tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Requirements CS 2349 and CS 23201
bull starting from a speed at least 10 kts above the stall speed bull longitudinal control must be pulled back bull rate of speed reduction will not exceed 1 knots (level stall) and 3 knotss (turning stall)
Tests have been performed in the following configurations and conditions
bull Maximum weight take offbull Engine running at 75 and idle bull Flap a 0⁰ 15⁰ and fullbull Landing gear retracted and extendedbull Trim speed ( = 15VS1)bull CG in the max forward and aft positionbull Turning stall with 30⁰ of bank
hellipleading to more than 100 stalls to accomplish certification requirements
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
P2006T aircraft
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
CS-23FAR-23 Certified
P2006T and other similar airplanes
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel tests
Scale Model (165)Fluorescent oil film visualizations
DIAS low-speed wind tunnelTest section 2 m times 14 m
Transitionstrips
Turbulence Intensitysim 01
Max speedsim 45 ms
Re asymp 06times106
In-FlightRe asymp 60times106
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Pitching moment coefficient measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different stabilator deflection angles δs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Lateral-directional coefficients measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different rudder deflection angles δr
Roll
Yaw
Side-force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
PitotProbe α - Flag
β - Flag
AHRSControl Unit (PC) GPS Antenna
Aileron Deflection PotentiometerSpaceAge Control Mini Air Data Boom
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Calibrations
COTS sensorΑngle α and β accuracy verified in wind tunnel 02 degUsed to calibrate aircraft pitotstatic system
Load cell calibration Then applied to the control stick
lsquoSpeed coursersquo technique evaluate CASCross check with differential GPS outputs
CAS vs IAS
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
AC Total Pressure Probe
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Stall tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Requirements CS 2349 and CS 23201
bull starting from a speed at least 10 kts above the stall speed bull longitudinal control must be pulled back bull rate of speed reduction will not exceed 1 knots (level stall) and 3 knotss (turning stall)
Tests have been performed in the following configurations and conditions
bull Maximum weight take offbull Engine running at 75 and idle bull Flap a 0⁰ 15⁰ and fullbull Landing gear retracted and extendedbull Trim speed ( = 15VS1)bull CG in the max forward and aft positionbull Turning stall with 30⁰ of bank
hellipleading to more than 100 stalls to accomplish certification requirements
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
P2006T and other similar airplanes
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel tests
Scale Model (165)Fluorescent oil film visualizations
DIAS low-speed wind tunnelTest section 2 m times 14 m
Transitionstrips
Turbulence Intensitysim 01
Max speedsim 45 ms
Re asymp 06times106
In-FlightRe asymp 60times106
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Pitching moment coefficient measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different stabilator deflection angles δs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Lateral-directional coefficients measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different rudder deflection angles δr
Roll
Yaw
Side-force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
PitotProbe α - Flag
β - Flag
AHRSControl Unit (PC) GPS Antenna
Aileron Deflection PotentiometerSpaceAge Control Mini Air Data Boom
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Calibrations
COTS sensorΑngle α and β accuracy verified in wind tunnel 02 degUsed to calibrate aircraft pitotstatic system
Load cell calibration Then applied to the control stick
lsquoSpeed coursersquo technique evaluate CASCross check with differential GPS outputs
CAS vs IAS
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
AC Total Pressure Probe
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Stall tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Requirements CS 2349 and CS 23201
bull starting from a speed at least 10 kts above the stall speed bull longitudinal control must be pulled back bull rate of speed reduction will not exceed 1 knots (level stall) and 3 knotss (turning stall)
Tests have been performed in the following configurations and conditions
bull Maximum weight take offbull Engine running at 75 and idle bull Flap a 0⁰ 15⁰ and fullbull Landing gear retracted and extendedbull Trim speed ( = 15VS1)bull CG in the max forward and aft positionbull Turning stall with 30⁰ of bank
hellipleading to more than 100 stalls to accomplish certification requirements
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Wind tunnel tests
Scale Model (165)Fluorescent oil film visualizations
DIAS low-speed wind tunnelTest section 2 m times 14 m
Transitionstrips
Turbulence Intensitysim 01
Max speedsim 45 ms
Re asymp 06times106
In-FlightRe asymp 60times106
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Pitching moment coefficient measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different stabilator deflection angles δs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Lateral-directional coefficients measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different rudder deflection angles δr
Roll
Yaw
Side-force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
PitotProbe α - Flag
β - Flag
AHRSControl Unit (PC) GPS Antenna
Aileron Deflection PotentiometerSpaceAge Control Mini Air Data Boom
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Calibrations
COTS sensorΑngle α and β accuracy verified in wind tunnel 02 degUsed to calibrate aircraft pitotstatic system
Load cell calibration Then applied to the control stick
lsquoSpeed coursersquo technique evaluate CASCross check with differential GPS outputs
CAS vs IAS
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
AC Total Pressure Probe
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Stall tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Requirements CS 2349 and CS 23201
bull starting from a speed at least 10 kts above the stall speed bull longitudinal control must be pulled back bull rate of speed reduction will not exceed 1 knots (level stall) and 3 knotss (turning stall)
Tests have been performed in the following configurations and conditions
bull Maximum weight take offbull Engine running at 75 and idle bull Flap a 0⁰ 15⁰ and fullbull Landing gear retracted and extendedbull Trim speed ( = 15VS1)bull CG in the max forward and aft positionbull Turning stall with 30⁰ of bank
hellipleading to more than 100 stalls to accomplish certification requirements
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Wind tunnel test results
Pitching moment coefficient measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different stabilator deflection angles δs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Wind tunnel test results
Lateral-directional coefficients measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different rudder deflection angles δr
Roll
Yaw
Side-force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
PitotProbe α - Flag
β - Flag
AHRSControl Unit (PC) GPS Antenna
Aileron Deflection PotentiometerSpaceAge Control Mini Air Data Boom
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Calibrations
COTS sensorΑngle α and β accuracy verified in wind tunnel 02 degUsed to calibrate aircraft pitotstatic system
Load cell calibration Then applied to the control stick
lsquoSpeed coursersquo technique evaluate CASCross check with differential GPS outputs
CAS vs IAS
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
AC Total Pressure Probe
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Stall tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Requirements CS 2349 and CS 23201
bull starting from a speed at least 10 kts above the stall speed bull longitudinal control must be pulled back bull rate of speed reduction will not exceed 1 knots (level stall) and 3 knotss (turning stall)
Tests have been performed in the following configurations and conditions
bull Maximum weight take offbull Engine running at 75 and idle bull Flap a 0⁰ 15⁰ and fullbull Landing gear retracted and extendedbull Trim speed ( = 15VS1)bull CG in the max forward and aft positionbull Turning stall with 30⁰ of bank
hellipleading to more than 100 stalls to accomplish certification requirements
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Wind tunnel test results
Lateral-directional coefficients measured for a fixed transition on wings nacelles and fuselage and a reference Reynolds number of 06times106 at different rudder deflection angles δr
Roll
Yaw
Side-force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
PitotProbe α - Flag
β - Flag
AHRSControl Unit (PC) GPS Antenna
Aileron Deflection PotentiometerSpaceAge Control Mini Air Data Boom
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Calibrations
COTS sensorΑngle α and β accuracy verified in wind tunnel 02 degUsed to calibrate aircraft pitotstatic system
Load cell calibration Then applied to the control stick
lsquoSpeed coursersquo technique evaluate CASCross check with differential GPS outputs
CAS vs IAS
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
AC Total Pressure Probe
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Stall tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Requirements CS 2349 and CS 23201
bull starting from a speed at least 10 kts above the stall speed bull longitudinal control must be pulled back bull rate of speed reduction will not exceed 1 knots (level stall) and 3 knotss (turning stall)
Tests have been performed in the following configurations and conditions
bull Maximum weight take offbull Engine running at 75 and idle bull Flap a 0⁰ 15⁰ and fullbull Landing gear retracted and extendedbull Trim speed ( = 15VS1)bull CG in the max forward and aft positionbull Turning stall with 30⁰ of bank
hellipleading to more than 100 stalls to accomplish certification requirements
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight data acquisition system
PitotProbe α - Flag
β - Flag
AHRSControl Unit (PC) GPS Antenna
Aileron Deflection PotentiometerSpaceAge Control Mini Air Data Boom
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Calibrations
COTS sensorΑngle α and β accuracy verified in wind tunnel 02 degUsed to calibrate aircraft pitotstatic system
Load cell calibration Then applied to the control stick
lsquoSpeed coursersquo technique evaluate CASCross check with differential GPS outputs
CAS vs IAS
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
AC Total Pressure Probe
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Stall tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Requirements CS 2349 and CS 23201
bull starting from a speed at least 10 kts above the stall speed bull longitudinal control must be pulled back bull rate of speed reduction will not exceed 1 knots (level stall) and 3 knotss (turning stall)
Tests have been performed in the following configurations and conditions
bull Maximum weight take offbull Engine running at 75 and idle bull Flap a 0⁰ 15⁰ and fullbull Landing gear retracted and extendedbull Trim speed ( = 15VS1)bull CG in the max forward and aft positionbull Turning stall with 30⁰ of bank
hellipleading to more than 100 stalls to accomplish certification requirements
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Calibrations
COTS sensorΑngle α and β accuracy verified in wind tunnel 02 degUsed to calibrate aircraft pitotstatic system
Load cell calibration Then applied to the control stick
lsquoSpeed coursersquo technique evaluate CASCross check with differential GPS outputs
CAS vs IAS
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight data acquisition system
AC Total Pressure Probe
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Stall tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Requirements CS 2349 and CS 23201
bull starting from a speed at least 10 kts above the stall speed bull longitudinal control must be pulled back bull rate of speed reduction will not exceed 1 knots (level stall) and 3 knotss (turning stall)
Tests have been performed in the following configurations and conditions
bull Maximum weight take offbull Engine running at 75 and idle bull Flap a 0⁰ 15⁰ and fullbull Landing gear retracted and extendedbull Trim speed ( = 15VS1)bull CG in the max forward and aft positionbull Turning stall with 30⁰ of bank
hellipleading to more than 100 stalls to accomplish certification requirements
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight data acquisition system
AC Total Pressure Probe
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Stall tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Requirements CS 2349 and CS 23201
bull starting from a speed at least 10 kts above the stall speed bull longitudinal control must be pulled back bull rate of speed reduction will not exceed 1 knots (level stall) and 3 knotss (turning stall)
Tests have been performed in the following configurations and conditions
bull Maximum weight take offbull Engine running at 75 and idle bull Flap a 0⁰ 15⁰ and fullbull Landing gear retracted and extendedbull Trim speed ( = 15VS1)bull CG in the max forward and aft positionbull Turning stall with 30⁰ of bank
hellipleading to more than 100 stalls to accomplish certification requirements
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Stall tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Requirements CS 2349 and CS 23201
bull starting from a speed at least 10 kts above the stall speed bull longitudinal control must be pulled back bull rate of speed reduction will not exceed 1 knots (level stall) and 3 knotss (turning stall)
Tests have been performed in the following configurations and conditions
bull Maximum weight take offbull Engine running at 75 and idle bull Flap a 0⁰ 15⁰ and fullbull Landing gear retracted and extendedbull Trim speed ( = 15VS1)bull CG in the max forward and aft positionbull Turning stall with 30⁰ of bank
hellipleading to more than 100 stalls to accomplish certification requirements
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Stall tests ∙ Typical time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
NO FLAP WITH FLAP landing conf
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Stall tests ∙ Entry rate effect
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level stall time histories ndash NO FLAPXcg 165 MAC (max forward)
S2ρV21
WzamaxLC =
S2ρV21
WsLC =
Static CLmax=125In cruise conf
(1)
(2)
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Stall test results
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Post-design modifications
Winglets installed
First prototype no winglets
b = 112 m S = 147 m2
b = 114 m S = 148 m2
pre-certification tests
certification tests
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Winglet design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initial climb tests with One Engine Inoperative(OEI) were unsatisfactory
Winglets designed to increase the aircraftrsquos induced drag factor e with a very low penalty in level flight performances
With respect to original wingWetted area is kept constantWing span b only 02 m higherWing area S is practically the sameSlight increase in ARΔe = 010 (estimates from WT exp)Slight increase of MTOW 20 kg
e
072082
(estimated)
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Winglet design ∙ Engine chart method
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
- Thrust Horsepower (THP) and Brake Horsepower (BHP) determined from level-flight tests and engine charts
- Net installed propulsive efficiency ηp determined bysemi-empirical formulationηp = 07 (low speed) divide 082 (high speed)
Wstd = MTOW
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Generalized VelocityParameter
Generalized PowerParameter
Wstd = MTOW
Winglet design ∙ Engine chart method
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Winglets effect on climb performance
Rate of Climb (at 800 ft)169 ftmin
Rate of Climb (at 800 ft)300 ftmin
With wingletsNo winglets
See [1] AIAA papers AIAA-2010-7513 and AIAA-2010-7947[2] Nicolosi F De Marco A Della Vecchia P ldquoFlight Tests Performances and Flight Certification of
a Twin-Engine Light Aircraftrdquo AIAA Journal of Aircraft Vol 48 No 1 January-February 2011
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Longitudinal static stability tests
When a trimmed condition is established the pilot applies a gradual pulling to the longitudinal control and then releases the stick slowly
Top required stabilator deflections for level flight (max fwd and max aft CG pos)
Bottom stick-fixed Neutral point estimation at different level flight speeds
stabilator
Stick force
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Steady headingsideslip tests
Average flight speed of 100 kt in cruise configuration
The airplane is kept for successive time intervals of approximately 10 seconds at different fixed sideslip angles
sideslip
aileron
rudder
bank
aileron
rudder
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Phugoid mode evaluation
Typical phugoid response and characteristic roots
Speed variation with respect to a trimmed condition in level flight at 110 kts
Obtained with a step stabilator deflection of minus4 deg kept for 10 seconds and set back to the original position
ζPh is calculated using the transient-peak-ratio (TPR) method
Damped period TPh 27 s
Damping ratio ζPh 009
Damped pulsation ωdPh 0233 rads
Natural pulsation ωnPh 0234 rads
Averaged damped oscillation parameters in the imaginary plane extracted over a number of time histories
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Short period mode evaluation
Typical short period responseangle-of-attack time history as a response to a lsquo3-2-1-1-typersquo stabilator input
Maximum slope (MS) method used to estimate the short period natural pulsation
(Kimberlin Ward and Strganac)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Short period mode evaluation
Averaged damped oscillation parameters in the imaginary plane extracted from a number of time histories (excited by lsquo3211-typersquo longitudinal command input)Time constant τSP 00088 s
Damping ratio ζSP 040
Damped pulsation ωdSP 3125 rads
Damped period TSP 184 s
Natural pulsation ωnSP 3410 rads
Natural frequency fnSP=ωnSP 2π 054 cps
CAP = ωnSP2 nα asymp mg ωnSP
2 ( Q0 S CLα ) = 1009
Within Level 1 range(Class I-B MIL-STD-1797A)
τSP = minus1 Zα = m ( Q0 S CLα )
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Dutch roll mode evaluationmultiple pedal doublets Single pedal doublet
Initial condition trimmed level flight at 110 kts
β(t)
Damped period TDR 325 s
Damping ratio ζDR 026
Damped pulsation ωdDR 193 rads
Natural pulsation ωnDR 200 rads
Time factor ηDR =ζDRωnDR 052 rads
Sideslip variation with respect to a trimmed condition in level flight at 110 kts
ζPh is calculated using the transient-peak-ratio (TPR) method
δr(t)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Aircraft parameter estimation
bull Key element a computer program that seeks to replicate recorded flight test time histories of output variables by varying a given set Θ of coefficients in a linearized model of the aircraft (Jategaonkar Matlab codes)
bull Most of the elements of Θ are the desired values of aircraft stability derivatives referred to a given flight condition
bull The selected technique of flight data analysis for the tests on P2006T aircraft is the one known as lsquoOutput Error Methodrsquo (OEM)
Schematic of the OEM
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Longitudinal model equations
State equations Observation equations
Inputs δs T (constant)
state variables V α θ q
Aerodynamic model
Unknown parameters(longitudinal)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Level flight thrust
lsquoEngine chartrsquo method to determine aircraft generalized required power PIWbull Uninstalled engine
chart bull Map rpm altitudebull prop efficiency chartbull AC actual Weight
VIW is a reduced CAS
Thrust estimationbull Determine linear fit bull Estimate drag from PIWbull T = D ( 08 divide 15 kN)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Scalar cost function
The Output Error Method is a relaxation procedure that can be summarized as follows1 A suitable initial set Θ0 of values is chosen for Θ2 System outputs y and the residuals (z-y) are computed the measurement
noise covariance matrix R is also estimated3 The cost-function J(Θ ) is minimized with respect to Θ by applying one of
the available nonlinear optimization methods4 Step 2 is iterated until convergence ie J(Θ ) has reached its minimum
Covariance matrix
Cost function
OEM procedure
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Lateral-directional model equations
State equations
Observation equations
Inputs δ a δ r V Q
state variables p r
Unknown parameters(lateral-directional)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Multiple longitudinal maneuvers
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Checking the converged results
Dotted curves are the results of simulation using the converged values of Θ lon
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Longitudinal aerodynamic coefficients
Wind Tunnel(Re = 060times106)
Semi-Empirical
Estimated(Re asymp 6times106)
CD 0 0027 - 00334
CD α (1rad) 0171 - 0222
CL 0 0153 - 0289
CL α (1rad) 45 - 4152
Cm 0 minus008 - minus0922
Cm α (1rad) minus080 - minus0871
Cm q (1rad) - minus1905 minus14799
Cm δe (1rad) minus1830 - minus1811
Wind tunnel result level flight test result and estimation result comparedWind tunnel and system identification output refers to a lsquofixedrsquo configuration
A Lift curve slope CL α = 385 radminus1 has been determined through level flight test at different speeds (with stabilator in different positions)
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Lateral-directional results
Dotted curves are the results of simulation using the converged values of Θ lat-dir
Multiple δ a δ r inputs
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Lateral-directional results
Wind Tunnel(Re = 060times106) Semi-Empirical Estimated
(Re asymp 6times106)
Cl p - minus0529 minus0281
Cl r - - 0057
Cl δa - minus0057 minus0045
Cl δr 00115 0014 00009
Cl β minus00573 minus0061 minus0029
Cn p - - minus0130
Cn r - minus0084 minus0106
Cn δa - - minus0009
Cn δr minus00631 minus00679 minus00304
Cn β 005 0096 00135
CY p - - 0254
CY r - - 0112
CY δa - 0 0127
CY δr - 0173 004
CY β minus0688 minus0563 minus0355
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Now some flight simhellip
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
bull Flight dynamics and control SW librarybull ~50000 lines of C++ codebull ~80 C++ classesbull In development since 1997bull Data drivenbull XML configuration files
What is JSBSim
httpwwwjsbsimorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FlightGear
httpwwwflightgearorg
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Team of main developers and a large base of users
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has found a variety of uses in industry and academia and has benefited from the exposure through feature requests shared expertise suggestions and trouble reports
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
JSBSim a data driven sw
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
The simplest use of JSBSim
include ltFGFDMExechgt Include the executive header int main(int argc char argv) Pass a script name via argv
JSBSimFGFDMExec FDMExec Instantiate the Executive bool result = true FDMExecLoadScript(argv[1]) Load a script while (result)
result = FDMExecRun() Run until the script completes
The above code will model anything from a ball an aircraft and a car to a rocket The vehicle and simulation run specifics are all read from configuration files coded in XML format
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Vehicle Configuration File Format
ltfdm_configgt ltfileheadergt hellip ltfileheadergt lt-- 0 or 1 instance --gt ltmetricsgt hellip ltmetricsgt lt-- 1 instance --gtltmass_balancegt hellip ltmass_balancegt lt-- 1 instance --gt ltground_reactionsgt hellip ltground_reactionsgt lt-- 1 instance --gtltexternal_reactionsgt hellip ltexternal_reactionsgt lt-- 0 or 1 instance --gtltbuoyant_forcesgt hellip ltbuoyant_forcesgt lt-- 0 or 1 instance --gtltpropulsiongt hellip ltpropulsiongt lt-- 0 or 1 instance --gtltsystemgt hellip ltsystemgt lt-- 0 to n instances --gtltautopilotgt hellip ltautopilotgt lt-- 0 or 1 instance --gtltflight_controlgt hellip ltflight_controlgt lt-- 0 or 1 instance --gtltaerodynamicsgt hellip ltaerodynamicsgt lt-- 1 instance --gtltinputgt hellip ltinputgt lt-- 0 or 1 instance --gtltoutputgt hellip ltoutputgt lt-- 0 to n instances --gt
ltfdm_configgt
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
45
GeometryMasses
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Initialization file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Script file
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Propulsion configuration files
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
FCS
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
JSBSim use in simulationndashbased design
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
JSBSim has been used in simulationndashbased aircraft design and analysis approachesThe focus is on the evaluation of aircraft as multi-state systems ie one having a finite set of performance levels or ranges Sometimes these ranges are differentiated by distinct levels of failure In order to accurately examine numerous aircraft performance states a multi-disciplinary design model is used a 6-DoF flight simulator integrated with a vortex lattice aerodynamics solver and a tool for calculation of weights and inertias The JSBSim batch running mode facilitates a global approach for concurrent analysis of aircraft expected performance and availability Namely by allowing systematic calculation of performance metrics for differing aircraft states the relationship between an aircrafts global design variables and its performance and availability may be established Such an approach allows designers to identify those elements that might drive system loss probability through an analysis of performance changes across system states and their respective sensitivity to design variables
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Aircraft integrated system model used at Draper Laboratorywith behavioralndashMarkov failure modelling
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Flight simulation ∙ JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
See [1] Berndt J S ldquoJSBSim An Open Source Flight Dynamics Model in C++rdquo AIAA 2004-4923 AIAA Modeling and Simulation Technologies Conference and Exhibit 16 - 19 August 2004 Providence Rhode Island USA
[2] Coiro D P De Marco A Nicolosi F ldquoA 6DOF Flight Simulation Environment for General Aviation Aircraft with Control Loading Reproductionrdquo AIAA 2007-6364 AIAA Modeling and Simulation Technologies Conference and Exhibit 20-23 August 2007 Hilton Head South Carolina USA
[3] Berndt J S De Marco A ldquoProgress on and Usage of the Open Source Flight Dynamics Model Software Library JSBSimrdquo AIAA 2009-5600 AIAA Modeling and Simulation Technologies Conference and Exhibit 10-13 August 2009 Chicago Illinois USA
[3] Agte J Borer N K de Weck O ldquoA Simulation-based Design Model for Analysis and Optimization of Multi-State Aircraft Performancerdquo AIAA 2010-2997 51st
AIAAASMEASCEAHSASC Structures Structural Dynamics and Materials Conference 12-15 April 2010 Orlando Florida
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Conclusions
The success story of P2006T aircraft postndashdesign modifications
Aircraft response modes and flight qualities
Parameter estimation of stability derivatives
Uses of the open source flight dynamics model software library JSBSim
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
Thank you
EWADE 2011 mdash 10th European Workshop on Aircraft Design Education 24 - 27 May 2011 Naples Italy
Thank youThank you
Thank youThank you
