Free-fall Autorotate?

[nosehair]

they may not cone to the point where they would break since they are in free fall and not working to lift the helicopter.

Probably true at the beginning when the blades are not turning, but when the start is attempted and the blades begin to turn and lift....

I think they would reach the same point of coning as they tun up as we know they will when turning down...

 

[Andy Neill]

Probably true at the beginning when the blades are not turning, but when the start is attempted and the blades begin to turn and lift....

I think they would reach the same point of coning as they tun up as we know they will when turning down...

nosehair,

I think you are giving too much credit for the amount of lift going on at flat pitch. The only portion of the baldes that will have positive pitch will be very near the root with the vast majority of the disc being driven with negative pitch due to blade twist.

I'm staying in the non cone-heads camp.

 

[sardaddy]

Rotors cone when they are spooling down because there is usually and armpit full of collective applied. I want to verify you mean coning and not drooping on that point.

The rotors don't cone in an autorotation even when the blades do spool down to about 1/3 of their normal rotation speeds if the operator screws it up. So, I don't think the dynamics applied at the bottom of a maneuver can be directly applied to the dynamics at the top but it is a good discussion.

 

[flyjetspeed]

The biggest problem with getting the rotor head moving would be stability. As soon as you went inverted everything that was working for you is now working against you. So you would need a way to keep the aircraft upright for the time needed to begin spooling up the rotor system. I would suggest a detachable cable from the rotor hub with a large parachute system like the old mercury capsules had and spin her up at flat pitch until in the green arc, then jettison. After that it's a walk in the park.

 

[Andy Neill]

I would suggest a detachable cable from the rotor hub with a large parachute system like the old mercury capsules had and spin her up at flat pitch until in the green arc, then jettison. After that it's a walk in the park.

I like it!

 

[phr8dawg]

I'll ride shotgun.