Download - Jar speeds & distances intro
2. SPEEDS AND DISTANCES2. SPEEDS AND DISTANCES
Performance JAR 23Performance JAR 23
SPEEDS AND DISTANCESSPEEDS AND DISTANCES
Speeds: Definitions
• VS: Stall speed
• VS0: Stall speed in landing configuration
• VS1: Stall speed in a specified configuration
• VLE: Maximum Landing Gear Extended speed
• VLO: Maximum Landing Gear Operating speed
• VFE: Maximum Flap Extended speed
• VA: Maneuvering speed
• VNO: Maximum Structural Cruising speed
• VNE: Never Exceed speed
• VR & V2: Operative speeds
Declared distances
Takeoff requirements
SPEEDS: DEFINITIONSSPEEDS: DEFINITIONS
STALL SPEED (VS)
It is the minimum steady flight speed at which the aeroplane is controllable.
Stall condition
SPEEDS: DEFINITIONSSPEEDS: DEFINITIONS
STALL SPEED IN LANDING CONFIGURATION (VS0)
It is the minimum steady flight speed at which the aeroplane is controllable under the following conditions:
• Propeller in takeoff position.
• Engine controls set at zero thrust.
• Landing gear down and cowl flaps closed.
• Full flaps.
• CG in the most unfavourable position (forward).
• Maximum Take Off Mass (MTOM).
SPEEDS: DEFINITIONSSPEEDS: DEFINITIONS
STALL SPEED IN A SPECIFIED CONFIGURATION (VS1)
It is the minimum steady flight speed at which the aeroplane is controllable under the following conditions:
• Propeller in takeoff position.
• Engine controls set at zero thrust.
• Specified configuration (the same for which the speed found will be used).
For single engined landplanes, VR must not be less than VS1.
SPEEDS: DEFINITIONSSPEEDS: DEFINITIONS
MAXIMUM LANDING GEAR EXTENDED SPEED (VLE)
It is the maximum calibrated airspeed at which the airplane can be safely flown with the landing gear extended. This is a problem involving stability and controllability.
MAXIMUM LANDING GEAR OPERATING SPEED (VLO)
It is the maximum calibrated airspeed at which the landing gear can be safely extended or retracted. This is a problem involving the air loads imposed on the operating mechanism during extension or retraction of the gear.
SPEEDS: DEFINITIONSSPEEDS: DEFINITIONS
MAXIMUM FLAP EXTENDED SPEED (VFE)
It is the highest calibrated airspeed permissible with the wing flaps in a prescribed extended position. This is because of the air loads imposed on the structure of the flaps.
MANEUVERING SPEED (VA)
It is the maximum speed at which the limit load can be imposed (either by gusts or full deflection of the control surfaces) without causing structural damage.
SPEEDS: DEFINITIONSSPEEDS: DEFINITIONS
MAXIMUM STRUCTURAL CRUISING SPEED (VNO)
It is the speed that should not be exceeded except in smooth air and then only when caution.
NEVER EXCEED SPEED (VNE)
It is the speed limit that may not be exceeded at any time. It is indicated by a red line in the airspeed indicator.
SPEEDS: DEFINITIONSSPEEDS: DEFINITIONS
VNE
VNO
VFE
VS
VS0
SPEEDS: DEFINITIONSSPEEDS: DEFINITIONS
ROTATION SPEED (VR)
The rotation speed VR is the speed at which rotation must be initiated
in order to attain V2 not later than at 50 ft.
SPEEDS: DEFINITIONSSPEEDS: DEFINITIONS
TAKEOFF SAFETY SPEED (V2)
The takeoff safety speed V2 is the speed that will allow the initial climb to be continued with a safe margin to stall. For single-engined aeroplanes (JAR 23), this speed is the higher of:
a) A speed that is shown to be safe under all reasonably expected conditions, including turbulence and complete engine failure.
b) V2 ≥ 1.2 · VS1
DISTANCESDISTANCES
DECLARED DISTANCES
TORA: Takeoff Run Available
TODA: Takeoff Distance Available
ASDA: Accelerate-Stop Distance Available
LDA: Landing Distance Available
Declared distances can be found in the AIP (AD section), and they are also included in the aerodrome charts.
DISTANCESDISTANCES
TORA (Takeoff Run Available)
It is the distance available as takeoff run, which is basically the length of the runway.
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TORA
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TODA (Takeoff Distance Available)
It is the TORA plus any clearway, which is an area beyond the runway, free of obstacles and under the Airport Authority Control. A typical clearway is the sea.
DISTANCESDISTANCES
TORA
CWY
TODA
DISTANCESDISTANCES
ASDA (Accelerate-Stop Distance Available)
It is the TORA plus any stopway. A stopway is an area beyond the runway which can be used for decelerating the aeroplane during an aborted takeoff, without the aeroplane being damaged.
Stopway CANNOT be used for landing calculations.
DISTANCESDISTANCES
STOPWAY
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SWY
TORA
ASDA
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LDA (Landing Distance Available)
It is the length of runway which is declared available and suitable for the ground run of an aeroplane landing.
It is also a declared distance, and it will be equal to the TORA if there is no displaced threshold. Stopways are not included in the LDA.
DISTANCESDISTANCES
TORA
LDA
DT
DISTANCESDISTANCES
CWY = 100 m
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NO SWY
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DISTANCESDISTANCES
DISTANCESDISTANCES
RWY
CWY
SWYDT
TORA
ASDA
TODA
LDA
TAKEOFF REQUIREMENTSTAKEOFF REQUIREMENTS
FIELD-LENGTH REQUIREMENTS
NO STOPWAY OR CLEARWAY TOD ≤ 0.8 · TORA
50 ft
Takeoff distance = 80 % TORA Safety margin
TAKEOFF REQUIREMENTSTAKEOFF REQUIREMENTS
FIELD-LENGTH REQUIREMENTS
TORA
SWY OR CWY AVAILABLE 0.77 · ASDA
0.87 · TODA
In other terms:
TOD ≤ TORA
1.30 · TOD ≤ ASDA
1.15 · TOD ≤ TODA
TOD ≤ the most restrictive of