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View Full Version : Rotation speed, angle, lift off point


911slf
15th Jan 2012, 09:27
I saw a discussion of this on tech log but as a non pilot I should perhaps post my question here.

Is it the case that you normally rotate through (say) 3 degrees per second at Vr and that this continues until you are in your desired climb attitude? So if for example you rotate through about 9 degrees and the aircraft leaves the ground at this point, you continue to (say) 15 degrees - which would have involved a tail strike but for the fact you are now airborne?

When I used to fly a hang glider I would hold the nose low when running until I could feel the glider wanting to fly, then allow the nose to find its own level with no control input at which point I would be flying.

Just for interest the rotation on landing a hang glider in nil wind gives about 60 (yes sixty) degrees nose up.

BOAC
15th Jan 2012, 10:42
So if for example you rotate through about 9 degrees and the aircraft leaves the ground at this point, you continue to (say) 15 degrees - which would have involved a tail strike but for the fact you are now airborne? - exactly. Assumptions are right speed, right weights and correct rotation rate.

On landing, 'Vref' (reference touchdown speed), will probably have an element of 'geometry' in it and normally one could still be flying much slower but with grinding noises from the tail.