Effect of prerotation on takeoff distance

XXavier

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Just to try that on Tuesday, when I have a gyro class with an ELA. How many meters are those 3,4 seconds, so I can use a ground reference?

Assuming during those initial 3,4 s a constant acceleration of 2-3 m/s2 (an interval that seems plausible to me) that's 12-18 meters more or less...

I hope my instructor won't complain...
 

Resasi

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...only when his knees start getting hammered by the stick.
 

Vance

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I feel that is bad advice Jean Claude.

I feel that is bad advice Jean Claude.

This is precisely what I said, Vance: Shorten the distance by more acceleration in the beginning, and monitor μ to avoid too much airspeed and not enough rotor rpm.
I said that my remarks are theoretical. A difficulty is introduced due to the landing gear of the Bensen clones, which tilts the gyro inadvertently during the run. Also, the fear threshold is not entered in my simulation. The practice would require appropriate instrumentation.
However the principle is not new. This was the procedure recommended for Cierva C30, as you can read in this A.R.C report 1859

That is precisely what I was advising against Jean Claude; too much forward speed without enough rotor rpm.

My advice is to follow the takeoff procedure in the Pilot's Operating Handbook for the gyroplane you are flying if there is one.

I don’t fly in theoretical air and in my experience the air I fly in is not as predictable as your theory.

I feel that risking flapping the blades for the potential benefit of shortening the takeoff roll slightly is poor technique.

The takeoff in a gyroplane is complicated enough without adding additional steps and pitfalls.

I feel those who are learning to fly a gyroplane should stick to the POH for that gyroplane.

If you are flying a Cierva C30 then follow that procedure.

Enough said.
 

Jean Claude

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All your points are good, Vance:
I do not encourage beginners to experiment with procedures that are unsuited to their aircraft.
I just encourage manufacturers and instructors to understand the procedure defined by true aerodynamicists like La Cierva.
 
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Vance

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All your points are good, Vance:
I do not encourage beginners to experiment with procedures that are unsuited to their aircraft.
I just encourage manufacturers and instructors to understand the procedure defined by true aerodynamicists like La Cierva.
Thank you Jean Claude, I was concerned your message of caution might be lost on inexperienced gyroplane pilots.
 
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