Aircraft Performance Report - Globalair.com

Aircraft Performance

Report

Prepared Exclusively For:

John Smith

City, State

November 8, 2012

Prepared by:

Conklin & de Decker Associates Inc.

1006 N Bowen Rd Suite B

Arlington, Texas 76012

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1970 (STC) original type certificate issuedYEAR TYPE CERTIFICATED:

Bombardier

LJ 24D

MANUFACTURER:

MODEL NUMBER:

AIRCRAFT NAME: Learjet 24D

N/A

PO Box 7707

-

-, - - ---

Page 1 of 9

1959

Gulfstream

GI

G-159

N/A

PO Box 2206

-

--

No 1976

24D 230 - 328

IN PRODUCTION:

SERIAL NUMBERS:

No 1969

1-200, except 13 and 113. 322-323

N.A.

REMARKS: In Production: 1970-1976

All as indicatedDATA SHOWN VALID FOR:

100/63A/C PRODUCED/IN SERVICE:

36,000 lb. TOGW optional on GI 1-163.

163 thru 200 and all that have the 36,000

196/67

RVSM: N.A.

CERTIFICATION BASIS: FAR 25 CAR 4B dated 12/31/53 as amended and SCAR

Learjet 24D, GI

Wichita, KS 67277 USA(316) 946-2000www.bombardier.com www.gulfstream.com

Savannah, GA 31402 USA(912) 965-3000

- Savannah International Airport

- -

-, - - -

Lear

jet 2

4D, G

I

1966 for LJ 24

529-8X engines optional on GI 1-165. In Production: 1958-1969

lb. TOGW option and 529-8Z engines.

No. 422A dated 7/02/58

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GENERAL DATA

Ramp Weight

Takeoff Weight

Landing Weight

Zero Fuel Weight

Basic Operating Weight

WEIGHTS GI

Lbs

13,500

11,880

11,400

7,830

13,800 36,000

36,000

34,285

27,303

24,500

Learjet 24D

Usable Fuel

Useful Load

Payload with Full Fuel

Maximum Payload

NBAA IFR Fuel Reserves (200 NMi Alternate)

5,628

5,970

342

1,760

3,570

12,017

-517

2,803

1,900

11,500

Manufacturer

Model

Thrust/Horsepower (SL Std.)

Thrust or Prop Reversers/Feathering

General Electric

CJ610-6

2,950

Optional

Rolls Royce

Dart 529-8X

1,900 (Wet)

No/Yes

POWERPLANT

EPNdB 85.8

103.7

95.3

No

0.0

0.0

0.0

No

Takeoff

Sideline

Approach

Meets Stage 3 Restrictions

FAR 36 NOISE LEVELS

VMC (Ground)

VMC (Air)

V2 (Max. Takeoff Gross Wt.)VREF (BOW + 4 Pax + NBAA Res.)

KIAS -

108

131124

91

101

114100

SPEEDS

Pressure Differential

--Sea Level Cabin to

--Cabin Alt at Max Cert. Alt.

6.6

15,500

8,000

PSI

Ft.

Ft.

8.9

24,000

8,000

PRESSURIZATION

Seats -- Crew

Passengers (Typical)

Passengers (Maximum)

Volume -- Total Pass. Cabin

Baggage -- Total

Internal

Main Door Size

2

12

12

1,100

100.0

100%

5.08 x 2.8

Cu. Ft.

%

Inch

2

5

7

192

40.0

4.16 x 3

ACCOMMODATIONS

Rate of Climb (MTOGW) -- All Engines

PERFORMANCE

1,900

560

25,000

24

14,600

Ft./Min

Ft.

Min.

Ft.

6,800

2,100

43,000

24

28,500

-- One Engine Out

Initial Cruise Altitide (MTOGW)

Time to Initial Cruise Altitude

Engine Out Ceiling (mid weight)

Maximum Range (Long Range Cruise) NMiKtsNMi

Kts

410899

876439

1,912285

1,866298

Average Speed (Long Range Cruise)Maximum Range (Maximum Cruise)Average Speed (Maximum Cruise)

EQUIPMENT

-

-

-

-

-

-

-

-

-

-

Avionics: Avionics System

Cockpit Voice Recorder

Flight Data Recorder

EICAS

Ground Warning System-

-

-

-

-

-

Traffic Warning System

Maint Diag Sys

VHF 8 Khz Spacing--

-

-

Other: Auxiliary Power Unit

Single Point Refuel

External Lavatory Service

-

-

100%

Lbs/SHP

NOT TO BE USED FOR FLIGHT PLANNING

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EXTERIOR

Learjet 24D - GI -

Scale = 1:200

Lear

jet 2

4D, G

I

Refer to the general data section for dimension unit of measure.

16.0

43.2

35.6

8.3

12.3

19.8

63.7

78.3

23.3

23.3

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INTERIOR

Learjet 24D - GI -

Lea r

jet 2

4D, G

I

Refer to the general data section for dimension and volume unit of measure.

Scale = 1:90

Baggage Volume:

1,100

100.0

192

40.0

Cabin Volume:

- Baggage

Learjet 24D GI

Scale = 1:50

9.0

3.0

4.44.95

35.6

5.4

7.4 6.1

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*4 Passengers for Jets and Turboprops * 2 Passengers for Pistons

BLOCK FUEL/TIME

Learjet 24D - GI -

Lea r

jet 2

4D, G

I

*4 Passengers for Jets and Turboprops * 2 Passengers for Pistons


* NBAA IFR Fuel Res. *ISA *No Wind

*NBAA Fuel Res. *ISA *No Wind

0 500 1000 1500 2000 25000

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000Block Fuel

Range (N. Mi.)

Blo

ck F

uel

(lb

s.)

Long Range - Solid

Max Cr. - Dashed

0 500 1000 1500 2000 25000:00

1:00

2:00

3:00

4:00

5:00

6:00

7:00

8:00

9:00

10:00Block Time

Range (N. Mi.)

Blo

ck T

ime

(Hrs

.)

Long Range - Solid

Max Cr. - Dashed

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BALANCED FIELD LENGTH

*Dry Level Runway *No Wind *NBAA IFR Fuel Res. *86° F

Learjet 24D - GI -

Lea r

jet 2

4D, G

I


0 500 1000 1500 2000 2500 30000

1000

2000

3000

4000

5000

6000

7000

8000

9000

10000Takeoff

Range (N. Mi.)

FA

R 2

5 B

alan

ced

Fie

ld L

eng

th (

ft.)

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TAKEOFF/LANDING

*4 Passengers *86° F for Jets and Turboprops

Learjet 24D - GI -

Lea r

jet 2

4D, G

I

4 Pax Jets and Turboprops, 2 Pax Piston


* 2 Passengers * 86°F for Pistons

(1) - FAR 91 Unfactored (2) Optional: FAR 91 Subpart K, FAR 135(3) Required: FAR 121, 135, FAR 91 Subpart K

0 1000 2000 30000

2000

4000

6000

8000

10000

12000

14000

16000Max Takeoff Elevation

Range (N. Mi.)

Ele

vati

on

(ft

.)

00

1000

2000

3000

4000

5000

6000Landing *Sea Level

Lan

din

g R

un

way

Req

uir

ed (

ft.)

Passenger Wt. -

Max Wt. -

-----1-----

-----2-----

-----3-----

-----1-----

-----2-----

-----3-----

-----1-----

-----2-----

-----3-----

-----1-----

-----2-----

-----3-----

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FLIGHT ENVELOPE

*4 Passengers *1/2 Total Fuel for Jets and Turboprops

Learjet 24D - GI -

Lea r

jet 2

4D, G

I

*4 Passengers *1/2 Total Fuel for Jets and Turboprops


*2 Passengers * 1/2 Total Fuel for Pistons

*2 Passengers * 1/2 Total Fuel for Pistons

0 100 200 300 400 500 6000

10000

20000

30000

40000

50000

60000

Max. Cruise Speed

True Air Speed (KTAS)

Alit

itu

de

(ft.

)

M= .60 .65 .70 .75 .80 .85

0 100 200 300 400 500 6000

10000

20000

30000

40000

50000

60000

Max. Op. Spd. (VMO/MMO)

True Air Speed (KTAS)

Alit

itu

de

(ft.

)

M= .60 .65 .70 .75 .80 .85

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PAYLOAD RANGE

*NBAA IFR Reserves

Learjet 24D - GI -

Lea r

jet 2

4D, G

I


0 500 1000 1500 2000 2500 30000

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

1000 lbs

2000 lbs

3000 lbs

Payload Range

Range (N. Mi.)

Pay

load

(P

asse

ng

ers

at 2

00lb

s)

Max Landing Weight

Max Landing Weight

2012 Conklin & de Decker Associates, Inc.

P.O. Box 1142 Orleans Massachusetts 02653508-255-5975 conklindd.com

GENERAL DATA: Weights: Maximum permitted as shown in the Limitation Section of the aircraft's Flight Manual. Maximum Ramp Weight: Specified during aircraft certification. It is the maximum weight authorized for taxiing/towing an aircraft on the ground. It is greater than the maximum takeoff weight due to the fuel that will be burned during the taxi and run-up operations. Maximum Take-Off Weight: Specified during aircraft certification. It is the maximum weight of the aircraft at take-off. Maximum Landing Weight: Specified during aircraft certification. It is the maximum permissible weight of the aircraft at landing. Zero Fuel Weight (ZFW): Specified during aircraft certification. The ZFW of an aircraft is the total weight of the aircraft and all its contents, without any fuel on board. This is a flight manual limitation based on the aerodynamic properties of the aircraft. Some aircraft under 12,500 pounds take-off weight may not have a specified ZFW in the aircraft limitations section. Basic Operating Weight (BOW): Is the empty weight, typically equipped, plus unusable fuel and liquids, flight crew @ 200 pounds each and their supplies. The flight crew includes the pilot(s) and flight engineer (if required). Useable Fuel: Is the Useable Fuel in gallons x 6.7 pounds per gallon (Jet fuel) or 6 pounds per gallon (AVGAS). Useful Load: Maximum Ramp Weight minus the Basic Operating Weight. Payload - Full Fuel: Is the Useful Load minus the Useable Fuel. Payload – Maximum: Is the maximum Zero Fuel Weight minus the Basic Operating Weight. NBAA IFR Fuel Reserves: Fuel for go-around at destination airport plus climb to 5,000 feet and hold for 5 minutes, fly to and land at alternate airport 200 NMi away and fuel to hold at 5,000 feet for 30 minutes. For Piston powered Fixed Wing aircraft this is calculated with a 100 NMi alternate. Powerplant: The thrust shown is maximum take-off thrust per engine under Sea Level, Static conditions. FAR 36 Noise Levels: The noise levels shown were obtained from manufacturer’s data. In order to meet FAR 36 Stage 3 requirements, the maximum noise level permitted is: Take-off 89.0 EPNdB. Sideline 94.0 Approach 98.0



Speed: The limitations shown are obtained from the Flight Manual Limitations section. Pressurization: Data is obtained from the aircraft specifications.

Accommodations: Passengers: For jets and turboprops it was determined that 4 passengers was a load any turbine aircraft, regardless of size, could

comfortably carry. Pistons are calculated utilizing 2 passengers.

Passenger Seating (typical): Shown for a typical corporate configuration. Seating capacity can vary significantly depending on interior layout selected. Passenger Seating (maximum): Obtained from the aircraft Flight Manual Limitations section. 19 seats is the limit to operate under Part 91 and without the required use of a flight attendant Total Passenger Cabin Volume: Measured from the cabin/cockpit separator to the aft pressure bulkhead, without chairs and other cabin furnishings. Total Baggage Volume: Can also vary greatly depending on interior layout. The number shown is for a typical interior. Internal Baggage Percent: Indicates what portion of the baggage compartment is accessible in flight. Reserve Fuel: How much reserve fuel should be carried in case the aircraft has to be diverted to an alternate location because of an emergency or inclement weather? Since the FAA has no standard, it was decided the NBAA Instrument Flight Rules (IFR) Reserve Standard of 200 Nautical Miles (NM) would be used for all turbine aircraft. Piston aircraft would be calculated with a 100 NM reserve. Winds and Temperature: The winds generally blow west to east worldwide. If flying north to south wind isn’t normally a factor. If flying east to west there is usually a head wind and with none traveling west to east. Because of these differences it was decided that the graphs would be calculated with no wind. We made the decision to use 86 degrees Fahrenheit (30 degrees Celsius) for take-off and landing calculations because this is the average summer temperature across a wide section of the United States because at the time this was where most of our customer base was located. The enroute (Cruise) portion is calculated at 59 degrees Fahrenheit (15 degrees Celsius) because this is what the majority of aircraft manufacturers use to calculate such performance. It is the International Standard Atmosphere. (ISA) Start /Taxi /Take-Off The Block Fuel/Time graphs are calculated from take-off to touchdown + 10 minutes for the whole trip plus fuel consumed. The ten minutes is used to account for start-up, taxi to and from the runway along with the take-off/ landing roll.



Climb Optimum climb to initial cruise altitude. Optimum climb data is from the aircraft operating manual. Optimum climb is whatever each aircraft manufacturer determines is optimum for their aircraft using aircraft forward speed, rate of climb and fuel consumption as a basis. Cruise Jet aircraft use the technique of gradually climbing in cruise altitude as fuel burns off and the aircraft becomes lighter. The altitude that provides the most fuel-efficient cruise at the start of a long flight, when the aircraft is fully loaded with fuel, is not the same as the altitude that provides the best efficiency at the end of the flight when most of the fuel aboard has been burned. The altitude at the end of a flight is usually significantly higher than at the beginning of the flight. By climbing gradually throughout the cruise phase of a flight, pilots can make the most economical use of their fuel. In the early days of jet aircraft, a simple cruise climb was used by pilots. This was a continuous, very gradual climb from an initial cruise altitude to a final cruise altitude and made the most efficient use of fuel. However, with increasing air traffic and the assignment of distinct flight levels to specific flights, it was no longer safe to cruise climb. A new method had to be adopted and is referred to as step climbing. Step climbing, with ATC approval, ensures the aircraft is always at an appropriate altitude for traffic control. While not quite as efficient as a continuous cruise climb, step climbs are still more efficient than maintaining a single altitude throughout a flight. The step climb intervals may be 1000, 2000, or 4000 feet, depending on the flight level rules which apply on the particular airway being flown. Step and cruise climbs are not normally applicable to lower-flying aircraft like those with piston and turboprop engines since their performance characteristics may be very different from those of jet aircraft. The most efficient altitude for a small general-aviation aircraft may be only a few thousand feet above the ground, and increasing altitude may diminish efficiency rather than improve it. We calculate cruise at long range cruise, or maximum cruise thrust with step climb to higher flight levels as fuel is burned off using 500 feet/minute minimum rate of climb as a basis for step climbing to the next numbered flight level. Example; a Falcon 20 may be able to climb at 500 feet/minute with a full load of passengers until it reaches 31,000 feet. Once there the aircraft would have to burn off fuel until it could climb at 500 feet/minute. When this is again possible the pilot would then get permission from ATC to climb to the next numbered flight level so it could continue to burn fuel more efficiently. Descent Optimum descent to destination airport. Optimum descent data is from the aircraft operating manual. Like optimum climb, optimum descent is whatever each aircraft manufacturer determines is optimum for their aircraft using aircraft forward speed, rate of descent and fuel consumption as a basis. Note: Fuel burn rates used in The Aircraft Performance Comparator do not include the same 15% add on utilized in the Aircraft Cost Evaluator. The extra 15% used in the Aircraft Cost Evaluator covers a wide range of items like ATC delays, APU operation and ATC flight delays. We assume optimum aircraft operating conditions when calculating the fuel burn for the graphs in the Aircraft Performance Comparator.



Fixed Wing Aircraft Graph Base Assumptions: Block Fuel/Time: “How much fuel does this aircraft require and how long will it take to fly a certain nautical mile trip?” This is a frequently asked question by aircraft buyers during the aircraft acquisition process. The Block Fuel/Time graphs answers these questions. All Block Fuel/Time data is calculated using the manufacturer’s published climb, cruise and descent data. Aircraft Performance Comparator Block Fuel/Time Graphs: Block Fuel/Time is separated into two graphs, Block Fuel and Block Time. The two graphs use an X, Y axis grid to make them easy to read. The Block Fuel graph is used to determine how much fuel in pounds (Y axis) is required for the distance shown in the Range (X axis). The Block Time graph is used to determine how long a trip (Y axis) would take using the Range (X axis). The user can see the aircraft data displayed based upon either long range cruise speed or maximum cruise speed. Long range cruise is based on the most efficient fuel burn; the speed an aircraft must fly to achieve maximum range. Maximum cruise is based on the fastest speed the aircraft can travel from point A to point B with no regard to fuel efficiency or range. Using the Block Fuel and Block Time graph examples below we can determine how much fuel and how much time is required for a 1,500 NM trip. It shows a long range cruise trip would require approximately 4,863 pounds of fuel using the Block Fuel graph and take just over 4 hours according to the Block Time graph. A max cruise trip would require approximately 4,900 pounds of fuel and take about 3.8 hours. One important factor the user could determine from these graphs is although the 1,500 NM trip takes longer to accomplish in long range cruise it also uses less fuel. If the fuel is required in gallons instead of pounds then divide the pounds of fuel by 6.7.



Balanced Field Length:

The Balanced Field Length (BFL) performance of aircraft can be very confusing. Most often the confusion arises from the basic differences in operating regulations governing the types of aircraft. There are two regulations that govern runway distance requirements for jets and turboprops. These regulations are FAR 23 (aircraft with a gross weight of 12,500 pounds and under) and FAR 25 (Air Transport Category aircraft with a gross weight over 12,500 pounds). These two regulations vary significantly. The more stringent rules of FAR 25 provide the passenger with greater safety margins than those used for FAR 23 private aircraft. For example, FAR 23 makes no allowance for loss of power or an engine or propeller failure. Additionally, the published distance requires no allowance for either being able to stop on the remaining runway or to continue the take-off on one engine after an engine failure. By contrast, FAR 25 regulations intended for Air Transport Aircraft such as business jets and large turboprops assures their passengers and crew that in the unlikely event of a loss of engine power during take-off the aircraft can either:

Stop within the remaining runway length

Take-off and climb on the remaining good engine.

This distance is known as Balanced Field Length. BFL is the distance obtained by determining the decision speed (V1) at which the take-off distance and the accelerate-stop distance are equal. Decision speed is the point where the pilot decides to either continue with the take-off or slam on the brakes and stop the aircraft. To illustrate how these regulations work let’s look at a typical situation involving a small turboprop (FAR 23) and a small business jet (FAR 25), both seating six passengers. We’ll assume maximum gross weight, sea level, International Standard Atmospheric (ISA) conditions and a dry, level, hard surface runway. Use the chart below. The small turboprop can legally take-off from a 2,600-ft runway operating under FAR 23. Although it has no requirement to consider an engine failure let’s assume an engine fails at its published rotation speed (Vr) of 94 knots. Rotation speed is the point when the aircraft starts to lift off the ground. Its distance to accelerate to Vr and stop is 3,400 ft, 800 ft longer than the take-off distance. If the take-off is continued after engine failure at Vr, then the runway required jumps to 4,750 ft, 82% longer than the take-off distance of 2,600 ft. Although 4,750 ft is the BFL for the turboprop it is not a legal requirement under Part 23 for runway length decision. The small business jet has a BFL of 4,500 ft runway in the same conditions, 250 ft shorter than the turboprop under the same contingencies and with the same margin of safety. Although the small business jet could take-off or accelerate/stop like the turboprop from a shorter runway the pilot is not permitted to base the runway length decision on anything other than the BFL data while operating under FAR 25.

Turboprop Jet

50 Ft 2,600 ft N/A

Accelerate/Stop 3,400 Ft N/A

BFL 4,750 ft 4,500 ft

Although the turboprop can legally take-off on shorter runways than most jets, FAR 23 doesn’t give the same safety margin as FAR 25.



Aircraft Performance Comparator BFL Graphs Our graphs show range vs. BFL. They demonstrate the range an aircraft has taking-off from a runway of “x” length. The Balanced Field Length data is for all jet and turboprop aircraft with a Maximum Take-off Gross Weight (MTOGW) of 12,500 pounds and greater. For twin engine turboprop and piston aircraft weighing less than 12,500 pounds we show accelerate stop/go data and take-off field length over a 50-ft obstacle data. For single engine turboprop and piston aircraft we show take-off field length over a 50-ft obstacle data. This graph was designed to answer questions the potential aircraft buyer might have: How far a particular aircraft can fly if taking off from an airport with a runway that’s x amount of feet in length? These graphs were designed to represent both low altitude and high altitude airports during the summer months. The BFL Graph below is used for jet aircraft, single engine turboprop and piston aircraft. Note the use of two different lines. The solid line shows aircraft range/runway length requirement at sea level and 86F and the dashed line shows aircraft range/runway length requirement at 5,000ft and 86F. In the graph example below the range is depicted using the” x” axis and the runway length requirement is depicted using the “y” axis.

BFL Graph 1

The BFL Graph below is used for twin engine turboprop and piston aircraft. It is slightly different from BFL Graph 1 because it adds a third dashed line. The solid and dashed lines are identical to the lines in jets BFL Graph except both of these lines assume only one engine operating with take off over a 50 foot obstacle. It is assumed the aircraft will keep traveling the entire trip. The third dashed line was added to show the aircraft range/runway length requirement and clearance over a 50 foot obstacle with both engines operating. Just like BFL Graph 1 the range is depicted using the” x” axis and the runway length is depicted using the “y” axis. Both graphs are read the exact same way. In the jets BFL Graph 1 above if the pilot wanted to fly the aircraft 3,000NM he/she would need an airport at sea level with a runway of a little over 4,000ft in



length. The same aircraft flying the same range taking off at an airport at 5,000ft would require a runway of at least 7,000ft (dashed line).

Turbine aircraft (jets and turboprop) assume gross take-off weight, four passengers and NBAA Fuel Reserves. Piston aircraft assume two passengers.



Max Take-off Elevation:

A potential aircraft buyer might ask “Will this aircraft fly me non-stop from Mexico City (Elevation 7,350 ft) to San Francisco? I am based in San Francisco (Elevation 131 ft) and fly to Mexico City regularly. My current aircraft can’t fly non-stop back to San Francisco from high altitude airports like Mexico City or others in South America.” Although the Balanced Field Length graph shows the take-off performance of an aircraft at sea level and 5,000 feet there are limitations. As weight, altitude and temperature increase, the amount of runway required for take-off increases. At some point of altitude + temperature, the aircraft may not have sufficient performance capability to be able to safely take-off and avoid obstacles on climb-out in the event of loss of engine power. The Max Take-off graph shows the take – off limitations of the aircraft when departing from high altitude airports at 86 degrees F. If an aircraft operator wants to take off from a high altitude airport with a full load of passengers then it’s likely weight must be removed to make up for the decrease in take – off performance. Fuel and cargo are two areas weight can be removed. If fuel load is decreased then so is the range of the aircraft taking off from that airport. Aircraft Performance Comparator Max Take - Off Elevation Graph Using the graph above note the aircraft can’t take off at any airport with an elevation over 10,000 feet. Note that once an airport altitude goes above 7,000 feet the range of the aircraft decreases. No matter how long the runway is the ranges shown on the “x” axis are the maximum ranges the aircraft can fly taking off from the corresponding “y” axis elevations with full maximum take – off weight.



Landing Runway Length: Like Balanced Field Length, the runway required for landing an aircraft can be very confusing because of the different regulations governing how the required runway length is calculated. The landing distance, as required by the regulations, is the distance needed to land and come to a complete stop from a point 50 feet above the threshold end of the runway. It includes the air distance required to travel from the 50 foot height to touchdown plus the stopping distance. (Maximum brakes, no thrust reversers) For FAR 91 operators (not for hire) there is no requirement for any additional safety margin. A different set of requirements exist for air carriers and commercial operators (FAR 121, FAR 91 subpart K and FAR 135). The required landing distance from the 50 foot height cannot exceed 60% of the actual runway length available. In all cases, the minimum airspeed allowed at the 50 foot height must be no less than 1.3 times the aircraft stall speed in the landing configuration. This speed is commonly called the aircraft’s VREF speed and will vary with landing weight. Under FAR 121, FAR 91 Subpart K and 135 an optional runway (normally the planned divert airport runway) the aircraft can land on within 80% of the available runway length is required. All landing distances are calculated assuming optimum landing conditions. No allowances are made for a variety of real world factors such as worn tires and brakes, non optimum runway conditions, one engine inoperative, etc. No allowances are made for thrust reversers. A FAR 91 operator can legally land on a runway without requirement for any margin to be left over after stopping. Our landing distances are shown for a sea-level runway, 86F (30C) using two weights: Jets and Turboprops:

- Four passengers, NBAA IFR Fuel Reserves for a 200 NM alternate

- Maximum Landing Weight

Pistons - Two Passengers, IFR Fuel Reserves for a 100 NM alternate - Maximum Landing Weight



Aircraft Performance Comparator Landing Field Length Graph

The aircraft shown in the Passenger Weight portion of the graph below requires 2,300 ft (----1----) of runway to land operating under FAR 91. This is the actual distance required to stop the aircraft with no additional margin. If the same aircraft is operating under the more stringent air carrier FAR 91 Subpart K, FAR 121 or FAR 135 regulation the requirement is 3,833 ft of runway (----3----). This is calculated by dividing 2,300 by 0.6. The alternate runway requires 2,875 ft (----2----) and is calculated by dividing 2,300 by 0.8. Aircraft landing at Max Weight always require more landing distance.



Flight Envelope:

The Flight Envelope is defined as the combinations of velocity (speed) and height (altitude) aircraft can safely fly. The Flight Envelope section is composed of two graphs; The Max Cruise Speed and the Max Operating Speed (Vmo/Mmo) graphs. While Vmo applies to all fixed wing aircraft, Mmo applies to jet aircraft only. The graphs are shown in Knots True Airspeed (KTAS) and Mach number 1.0 being the speed of sound. The Max Cruise Speed is the maximum cruise speed of the aircraft at various altitudes. Max cruise speeds are limited by the ability of the aircraft engines to propel the aircraft forward in level flight vs. drag of the airframe. Max Cruise speed should always be less than Vmo/Mmo. The Max Operating Speeds, Vmo and Mmo, are limiting speeds associated with the structure of the aircraft. Vmo and Mmo shows how fast (or the never exceed speed) and high an aircraft can safely operate without becoming unstable for flight or suffer structural failure. Vmo is Maximum Operating limit speed expressed in knots indicated airspeed (KIAS). Mmo is Maximum Mach Operating Speed expressed in a Mach number (aircraft speed relative to the speed of sound). Mmo is the maximum Mach speed at which an aircraft can fly. Mmo is normally the same at all altitudes but at lower altitudes the aircraft will reach Vmo limits long before it reaches Mmo limits. This is because the aircraft reaches the maximum dynamic pressure it can withstand due to higher air density at lower altitudes. Exceeding Vmo and aircraft dynamic pressure thresholds will possibly cause structural failure. In general, the aircraft maximum speed increases as it gains altitude. The density of the air and the dynamic pressure on the aircraft decrease enabling the aircraft to travel at higher speeds safely. The maximum allowable speed will increase until the aircraft reaches Mmo. If the aircraft exceeds Mmo, changes to the airflow over the flight control surfaces will eventually lead to deterioration in control of the aircraft. As the aircraft climbs, at some point Vmo will be equal to Mmo. This normally occurs between 20,000 – 30,000 feet. Because the aerodynamic properties change as the aircraft climbs above this point; the limiting speed changes from Vmo to Mmo. Let's look at an example. A fictitious aircraft has a Vmo of 330 KIAS and an Mmo of 0.84 Mach. At sea level the speed of sound is 661.5 knots. If we use the standard atmosphere data and calculate Vmo to a Mach number at sea level, it would be 0.5. Mach 0.5 is less than the aircraft’s Mmo of 0.84. Now we go to 20,000 feet. According to the standard atmosphere data, the air density is 0.5328 times the density at sea level. If we are flying at our speed of 330 KIAS it would calculate to 452 KTAS. At 20,000 feet, the speed of sound is 614.3 KTAS, (Mach 1.0) slower than the speed of sound at sea level. At 20,000 feet, 452 KTAS is equal to Mach 0.736, still below our Mmo of 0.84. 26,000 feet is the altitude where the aircraft Vmo of 330 KIAS equals 503 KTAS. This also equals the aircraft Mmo of Mach 0.84. This is the aircraft’s fastest allowable airspeed. Now that the aircraft is now using Mmo we climb to 30,000 feet. The air density is now 0.3741 times the density at sea level. The speed of sound at 30,000 feet is 589.3 KTAS. Our limiting speed of Mach 0.84 calculates to 495.0 KTAS. In summary, at sea level, we can fly at 330 KTAS, at 26,000 feet we can fly at a speed of 503 KTAS. At 30,000 feet, we can fly at a speed of 495 KTAS. The fastest true airspeed this example aircraft can fly is 503 knots at 26,000 feet.



Aircraft Performance Comparator Flight Envelope Graphs Maximum Cruise Speed: This graph shows the maximum speed the aircraft is capable of flying based on maximum cruise thrust at the given weight and altitude. In the graph below note the aircraft has a maximum cruising speed of 490 Knots True Airspeed (KTAS) at 27,750 feet and 460 KTAS at 45,000 feet according to the Max Cruise Speed graph below.



Max Operating Speed: In the graph below the Mach lines are shown. Note how as altitude increases the speed of sound (Mach) decreases. Also note that at approximately 37,000 feet and above mach remains constant.



In the graph below note 30,000 feet is the point where Vmo is equal to Mmo. The aircraft can fly 490 KTAS safely in Vmo at 30,000 feet. Once in Mmo the aircraft can fly safely at Mach 0.84 at 45,000 feet.



Payload Range:

An aircraft buyer might need to know if they can fly a certain nautical mile trip with a certain number of passengers. The payload range graph was created to show the range of an aircraft with different numbers of passengers or pounds of payload. The range shown with zero passengers is the maximum (ferry range) of the aircraft. Our assumptions include a full load of fuel to include reserves, two pilots (unless otherwise specified) and no headwind for all fixed wing aircraft. A potential aircraft buyer might also need to know what range a jet aircraft can fly after a short repositioning flight without refueling or adding additional passengers after landing. For example, the aircraft departs a small airport outside Sacramento, CA on an international trip. The home airport does not have customs. The aircraft lands at San Francisco solely to clear Customs. It does not refuel. How far can it fly? The maximum landing weight line was added to the Payload Range graph to show the range an aircraft could fly if it took off at maximum landing weight with varying numbers of passengers instead of taking-off at the max take-off weight (MTOW). Aircraft Performance Comparator Payload Range Graph In the Payload Range graph below the aircraft shown has a ferry range of 3,270 NM. The range with eight passengers is 3,070 NM. The range at max landing weight and eight passengers is 2,070 NM.

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Aircraft Performance Report - Globalair.com