Take off Flashcards
(11 cards)
What is the definition of critical engine ?
‘Critical Engine’ means the engine whose failure would most adversely affect the performance or handling qualities of an aircraft”, i.e. an outer engine on a four engine aircraft.
What is V1 ?
V1 is the maximum speed at which the crew can decide to reject the takeoff, and is ensured to stop the aircraft within the limits of the runway.V1, in terms of calibrated airspeed, is selected by the applicant; however, V1 takes into account the speed gained with the critical engine inoperative during the time interval between the instant at which the critical engine is failed, and the instant at which the pilot recognises and reacts to the engine failure, as indicated by the pilot’s initiation of the first action (e.g. applying brakes, reducing thrust, deploying speed brakes) to stop the aeroplane during accelerate-stop tests.”
Vmcg is always less/ more than V1
Less than
What is Vr
Vr is the speed at which the pilot initiates the rotation, at the appropriate rate of about 3° per second.VR, in terms of calibrated air speed, […] may not be less than:
• V1,
• 105% of VMCA. Vr ≥ 1.05 VMCA
• The speed that allows reaching V2 before reaching a height of 35 ft above the take-off surface, or
• A speed that, if the aeroplane is rotated at its maximum practicable rate, will result in a [satisfactory] VLOF”
What is VLOF ?
VLOF is the calibrated airspeed at which the aeroplane first becomes airborne.” Therefore, it is the speed at which the lift overcomes the weight.
What is the relation between Vlof and Vmu ?
VLOF [must] not [be] less than 110% of VMU in the all-engines-operating condition and not less than 105% of VMU determined at the thrust-to-weight ratio corresponding to the one-engine-inoperative condition.”
When is the ac said to be geometrically limited ?
An aircraft is said to be geometrically-limited, when, at its maximum angle of attack during rotation (the tail of the aircraft hits the ground while the main landing gear is still on ground), the maximum lift coefficient is not reached.
V2 is the minimum climb speed that must be reached at a height of 35 feet above the runway surface, in case of an engine failure.
V2min, in terms of calibrated airspeed, may not be less than:
• 1.13 VSR
1 (JAR) or 1.2 VS (FAR) for turbo-jet powered aeroplanes […]
• 1.10 times VMCA
(c) V2, in terms of calibrated airspeed, must be selected by the applicant to provide at least the gradient of climb required by JAR 25.121(b) but may not be less than
• V2min; and
• VR plus the speed increment attained before reaching a height of 35 ft above the take-off surface.”
How is V2 represented on the speed scale ?
This speed must be entered by the crew during flight preparation, and is represented by a magenta triangle on the speed scale
Vmbe - Max brake energy
When the takeoff is aborted, brakes must absorb and dissipate the heat corresponding to the aircraft’s kinetic energy at the decision point. Brakes have a maximum absorption capacity, known as maximum brake energy. For certification purposes, this absorption capacity must be demonstrated with worn brakes -with no more than 10% of the allowable brake wear range remaining on each of the aeroplane wheel brakes.
- V1 ≤ VMBE
Maximum Tire Speed: VTIRE
The tire manufacturer specifies the maximum ground speed that can be reached, in order to limit the centrifugal forces and the heat elevation that may damage the tire structure. VLOF ≤ VTIRE. For almost all Airbus aircraft models, VTIRE is equal to 195 knots (Ground Speed).
