Rotax clutch experience?

[chuter]

Does anyone have any experience with the Rotax C gearbox with the centrifugal clutch? I'm mainly thinking of the prop freewheeling at idle while in a descent; any complaints? General recommendations?

[Chuck Irby]

I have a clutch in my C box behind a 618, and it works great. My son has one in his C box behind a 503. Mike Solano has one behind his F30. I, and my son both pull start our engines and it's a real advantage in starting, and the machines don't try to leave without us. The prop doesn't start to spin til about 2500 r's.

[chuter]

Thanks Chuck, so far the only negative comments I can find on the Internet are from fixed wingers that say it adds a lot of drag when they're descending with the engine at idle, but I figure that's probably not a problem for a gyro.

[quadrirotor]

It could be a BIG problem!....

[Chuck Irby]

What experience do you have with this clutch Andre', and how could it be a big problem?

[Chuck Irby]

Andre, Would you please answer my last post about the "C" box clutch?

[quadrirotor]

In flight, if the prop is idling (after an engine stop at high speed) and dragging and especially if the thrust (drag) line is beneath the C.G. (the rotor don't drag very much at high speed, the AoA of the rotor is less and less as the speed goes up) you could be in trouble which could lead in a bunt over if you don't react very quickly...so contrary to an airplane, when the engine of the gyro stops, you must pull on the stick (airplane pilot reflex must be reeducated)...

[Chuck Irby]

Andre', I apologize, but I don't fully understand your explanation. How can the prop be idling after the engine stops. Or, by "idling", do you mean that the prop is freely turning, and that would create more drag than a prop that was not turning?

I have pulled my throttle back to idle (2000 rpm), while at 500 feet AGL, thus allowing the prop to spin freely. This caused abosolutely no problem with my machine.

Andre, what gyro's do you have experience with?

[quadrirotor]

Can someone give the exact
drag quantity of an idling prop (free wheeling, centrifugal clutch, engine out)?