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AE-705 Introduction to Flight Lecture No 14 Capsule-07
AE-705: Introduction to Flight
Level Turn & Pull-up Maneuver
Udit VohraAerospace Engineering Department
PEC University of Technology,
Chandigarh
AE-705 Introduction to Flight Lecture No 14 Capsule-07
LAYOUT
• Coordinated Turn
• Turning flight parameters
• Fastest turn
• Tightest turn
• Turning in vertical plane
AE-705 Introduction to Flight Lecture No 14 Capsule-07
LETS FLY IN A LOOP
Watch the video carefully
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Watch the water level during the turn !
AE-705 Introduction to Flight Lecture No 14 Capsule-07
COORDINATED TURN
How do they do that ?
AE-705 Introduction to Flight Lecture No 14 Capsule-07
1. Constant Altitude
2. Banking of the a/c in horizontal plane
3. No tangential acceleration
4. Turn without a sideslip
5. Coordination b/w Ailerons and Rudder
Coordinated Turn
Use of Rudder in
a turn … why ??
Rudder for
yaw and
ailerons to roll
we will see that later on
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Adverse Yaw
The reason why we use rudder in a turn
http://www.boldmethod.com/learn-to-fly/aerodynamics/the-aerodynamics-of-a-turn-in-an-airplane/
AE-705 Introduction to Flight Lecture No 14 Capsule-07
TURNING FLIGHT EQUATIONS
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Equations of motion
ϕ
ϕ
L
W
LCosϕ = W ----(1)
LSinϕ = mV2
R----(2)
(2) / (1)
Tanϕ =V2
Rg
n = L
W( load factor)
n = 1 Cosϕ = Secϕ
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Turning Flight Parameters
Banking Angle
Φ = Cos−1( 1 n)
Related to turn rate
Steady coordinated turn is
not possible without
banking the a/c
Load Factor (n)
n = L
W
Depends on aircraft design
parameters
Represented in g’s
AE-705 Introduction to Flight Lecture No 14 Capsule-07
turn radius
mV2
R=
WV2
g R=
W n2 − 1
R = V2
g n2−1
Turn Radius
depends on V and n
R
R
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Turn rate
ω = dθ
dt=
V
R
ω = g n2−1
V
Turn Rate
depends on V and n
ω
ω
Degrees travelled per secSimilar to Angular Velocity
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Effect of bank angle
Pilot’s Handbook of Aeronautical Knowledge
Bank angle in a turn results in:
• Higher rate of turn
• Smaller radius of turn
• Higher loading on the wings
• Higher stall speed
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Fastest turn
• Max. turn rate
• Measure of a/c’s maneuverability
• Depends on a/c design parameters
V should be min
n should be max
Sustained turn rate when
• Thrust/weight
• Wing loading
• Aspect Ratio
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Tightest turn
• Min turn radius
• Measure of maneuverability
• Depends on design parameters
V should be min
n should be max
What is Vmin and nmax ??
What are constraints on nmax
Find out yourself !
Report on Moodle
Instantaneous turn rate when
• Thrust/weight
• Wing loading
• Altitude
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Continue..
http://people.clarkson.edu/~pmarzocc/AE429/AE-429-12.pdf
AE-705 Introduction to Flight Lecture No 14 Capsule-07
http://people.clarkson.edu/~pmarzocc/AE429/AE-429-12.pdf
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Instantaneous & Sustained turn
• Dogfight are generally dependent on rate of turn
• Aircraft which can turn faster will get into an
advantageous firing position quickly
ITR is a measure of how quickly an aircraft is able
to turn at the beginning of the turn
The turn rate which can be maintained for a period of
time is called the STR (Sustained turn rate)
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Tejas vs. F-16
v/s
Which one is better
and how?
What do you think ?
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Continued..
https://www.quora.com/search?q=instantaneous+turn+of+an+aircraft
Depends on wing
loading & Thrust to
weight ratio
Tejas wing loading: 247
kg/m²
F-16C Block 50 wing
loading: 431 kg/m²
Lesser the wing
loading more will be
the ITR
AE-705 Introduction to Flight Lecture No 14 Capsule-07
At horizontal plane STR, ITR > STR
the LCA outperforms the F-16A/B at high Mach numbers
and the F-16C/D under all Mach number regimes.
http://thebetacoefficient.blogspot.in/2015/04/lca-tejas-versus-f-16-in-combat-part-i.html
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Tejas v/s F-16
T:W is favorable for the F16, though the difference is smaller
(1.09 v/s 1.07 )
STR of F-16 > Tejas at slower speeds (< M = 0.65)
Tejas dominates at speeds greater than 0.65
• Dogfights generally happen at M > 0.65
• @ M < 0.65 Tejas = F-16
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Outcome of a dog-fight is difficult to predict
because it depends on
• the pilot,
• the initial positions of the aircraft
• the aircraft specs.
Tejas will dominate the F-16 in a majority of engagements
based on the aerodynamic characteristics
Made in INDIA
AE-705 Introduction to Flight Lecture No 14 Capsule-07
TURNING IN VERTICAL PLANE
Source: https://giphy.com/
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Turning in Vertical plane
• Aerobatic and combat a/c maneuvers
• Required during takeoff and landing
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Pull-Up Maneuver
Flight along a curved path with altitude increasing
Fr = L – W = W( n - 1)
Fr= mV2
R
R =V2
g(n−1)
ω = g(n−1)
V
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Dive Pullout
Part of descent flight
pilot_handbook_2016.pdf
• During this nose-down attitude,
the AOA and the airspeed
• The smooth flow of air over the
wing begins again, lift returns,
and the aircraft begins to fly
again.
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Team Assignment No 4
Design and Fabrication of a Glider
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Design a Glider for max. Range & Endurance
Launch from third floor of Foyer in LHC
No limit on material, or dimensions
Best of two launches for each Team
Technical Report to be submitted
Relative Scoring Scheme (to be announced)
Glider Design Competition
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Location of the Competition
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Example
AE-705 Introduction to Flight Lecture No 14 Capsule-07
Professional flyers
How do birds turn during a flight ?
Aerodynamics of Avian Flight
No Ailerons No vertical tail
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