I have always been wondering whether we can rotate before v1 as we have reached the appropriate speed to be airborne.Since V1 is just to advise you that you do not have enough runway to reject the T/O,is rotating before V1 okay?
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I think you should wait until you reached V1 speed before commencing Takeoff. Maybe a Real World Pilot can give us an explanation regarding this?
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Well.Conveniently,I can asked my Father who flys a A333!I will go ask him and tell you his answer to this.
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As far as I understand V1 is the decision speed/point of no return
At V1 there is not enough runway left to abort the takeoff, short of dual engine failure etc we are getting off the ground.
Vr is rotate speed untill you hit Vr you cant get off the groundā¦
Im not a pilot so what would I knowā¦
Vr is a little like 88 mph in the DeLorean, untill 88 mph (or Vr) not much really happens
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Yup agree.Before V1 will cause the aircraft to strike the tail.The aircraft will rotate but not be airborne .
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In the context of aviation āRotateā and ābecome airbourneā seem to be used fairly interchangeably.
So it hasnt really ārotatedā if it hasnt became airbourne,
If we are using the term ārotateā to mean nose wheel off the ground then pull back hard enough then im sure the nose will pick up once you have a reasonable amount of airflow over the elevators.
@Heavydriver has said some good stuff in the past about holding the nose off the ground for x amount of time before the mains lift off and could add something to this perhaps.
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Ok thanks for the information man!
You can rotate before v1. but there is a good chance your tail would strike the ground.
Boeing and Airbus tests this for all their aircraft with the Minimum Velocity Unstick test:
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Just like what everyone else said on this fourm, after you rotate V1, you are committing to takeoff. There is no turning back. This is the definition of V1 āThe speed beyond which the takeoff should no longer be aborted.ā
Watch this video made by CaptainJoe about V1 & V2:
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V1 was properly explained above as the speed at which a safety decision must be made by. At or above V1 rehecting a takeoff becomes and experiment in physics and pilot ability. With regards to the aircraft having ebough flying speed at V1 to lift offā¦ well it may in smaller aircraft but in most turbojet aircraft youād quickly find youself in a stalled situation. Vr is the speed at which the airplane has attained āflying speedā and a safe rotation can be made. It doesnt mean at this speed the wheels have left the ground it is the speed at which one can begin rotation.
Old school Pilots more often than not leave the actual surface at higher speeds than Vr due to rotation rate. This doesnāt mean that if your Vr is 167 that you leave the surface at 200ktsā¦ but a climb out at 170>175 should be expected.
Iād go into further details but each airplane is different in terms of what V2 speeds are so i digress
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While V1 depends on runway length and Vr does not, the answer is yes.
If the available rwy is much longer than the required rwy of your aircraft in its current configuration by the actual weather, there is no reason to wait for V1 before you rotate.
Try in a Cessna to start, fly, and land on a 10000+ft rwy. It works.
Yup.I clock in 150 knots in 10 secs and only cover 1/3 of the runway.
Oh this older test! I remember during the development of the a380 where the simulated tail strike actually became a tail strikeā¦
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Does anyone know of any takeoffs that have been aborted after V1 and how did they end up?
They would have to rotate.Since V1 advises you that there is no point of return,regardless of any failures,the pilot still has to rotate
If V1 is higher than VR, then V1 becomes VR. You can see this if you look up V1/VR/V2 table on this forum, click on the spreadsheet and see that on light planes V1=VR. It would be unsafe to reject a takeoff last VR. A Cessna on a 40,000 foot runway would have V1 and VR at somewhere around 55kias
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Remember to not use 100% throttle, try to keep N1 at 90%
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Ah the famous runway where cars try to bring your plane down with bunch of harpoons. I think you mean 4,000 feet. š
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