Vspeeds technical Flashcards
Vmcg is relevant only to -
Vmcg increases with -
Rudder effectiveness
Increasing density
Define Vgo -
VGO is the lowest decision speed from which a continued take-off is possible within the take-off
distance available.
Define Vstop -
VSTOP is the highest decision speed from which the aeroplane can stop within
the accelerate-stop distance available
Define Vef -
The difference between Vef and V1?
The calibrated airspeed at which the critical engine is assumed to fail. It is used for the purpose
of performance calculations. It is never less than VMCG
V1 take into account a 1 second reaction time from the crew
There are some rules about the speed for V1:
• may not be less than ____ plus the speed gained with the critical engine inoperative for the
time between engine failure and the point at which the pilot applies the first means of
retardation
• must not exceed __
• must not exceed ____
• must not be less than ____
There are some rules about the speed for V1:
• may not be less than VEF plus the speed gained with the critical engine inoperative for the
time between engine failure and the point at which the pilot applies the first means of
retardation
• must not exceed VR
• must not exceed VMBE
• must not be less than VMCG
Factors influencing V1 and magnitude of each:
- Increasing weight will increase v1
- Less flap will increase v1
- Decreasing density increases v1
- Downslopes decrease V1 and upslopes increase v1
- tailwinds reduce v1 and headwinds increase v1
Define VMBE -
is the maximum brake energy speed and it represents the maximum speed on the ground from which an aeroplane can safely stop within the energy capabilities of the brakes.
VMU is the -
However -
slowest calibrated airspeed at which the aeroplane can safely lift off the ground, and continue the take-off
despite VMU being the lowest speed the aeroplane can safely lift off the runway, in actual operating conditions, the aeroplane does not lift off at this speed. The aeroplane is flown so that it actually lifts off at a slightly faster speed. The reason is because VMU is very close to the stall speed, the aeroplane controllability is very “sloppy”, and lastly, in order to actually lift off at VMU some fairly dramatic actions take place which may be uncomfortable for the passengers.
The actual speed the aeroplane will lift off, in operational flights, is called VLOF and we will discuss this speed later.
Define Vmca -
The air minimum control speed. The minimum flight speed at which the aeroplane is controllable, with a maximum of 5° bank, when the critical engine suddenly becomes inoperative with the remaining engine(s) at take-off thrust. Although VMCA is the minimum control speed in the air, the factors that affect VMCA can for the purpose of the exam, be assumed to be the same as for VMCG.
VR may not be less than:
• __
• ___ VMC
• a speed such that __ may be attained before __ ft.
• a speed such that if the aeroplane is rotated at its maximum practicable rate the result will
be a VLOF of not less than 1.1VMU (all engines operating) or 1.05VMU (engine inoperative) [ if
the aeroplane is geometry limited or elevator power limited these margins are 1.08VMU (all
engines) and 1.04VMU (engine inoperative)]
VR may not be less than:
• V1
• 1.05VMCA
• a speed such that V2may be attained before 35 ft.
• a speed such that if the aeroplane is rotated at its maximum practicable rate the result will be a VLOF of not less than 1.1VMU (all engines operating) or 1.05VMU (engine inoperative) [ if the aeroplane is geometry limited or elevator power limited these margins are 1.08VMU (all engines) and 1.04VMU (engine inoperative)]
Factors that effect Vr:
- Vr increases with mass
- Vr increases with decreasing flap
- Vr increases with decreasing density
- upslope increases v1 and vice-versa
Define Vlof:
VLOF is the calibrated airspeed at which the aeroplane first becomes airborne which is at the moment when the main wheels have left the runway. VLOF should be faster than the minimum unstick speed VMU. The margin above VMU is determined by several factors.
V2min definition -
V2MIN may not be less than:
• ___VSR for 2 and 3 engine turboprops and all turbojets without provision for obtaining
a significant reduction in the one engine inoperative power-on stalling speed OR ___VSR
for turboprops with more than 3 engines and turbojets with provision for obtaining a
significant reduction in the one engine inoperative power-on stalling speed.
• ___VMC
The minimum take-off safety speed, with the critical engine inoperative.
V2MIN may not be less than:
- 1.13VSR for 2 and 3 engine turboprops and all turbojets without provision for obtaining
a significant reduction in the one engine inoperative power-on stalling speed OR 1.08VSR
for turboprops with more than 3 engines and turbojets with provision for obtaining a
significant reduction in the one engine inoperative power-on stalling speed. - 1.1VMCA
- 1.2 VS
- 1.15VS for turbo-prop more than 3 engines
V2 may not be less than:
- V2MIN
* VR plus the speed increment attained up to 35 ft.
VREF:
reference landing speed
Must be at least 1.23 VSRO and must be maintained down to 50 ft height
· Class A 1.23 VS
· Class B 1.3 VS
