Redundancy

[Quadcopter102]

Used to work on airplanes, none of them glide when the fan stops, that's why we called them lawndarts.

Helicopters on the other-hand can glide, it is called auto-rotation. smile

Even without a tail rotor??

 

[SteveMann]

I do sir, 1 big fan on top and a tiny one at the back to stop it becoming a spinning top.
I recall a newsreport video on TV some years back - about a chopper over NYC - the tail rotor ( I forget which) was either hit by another news chopper or building...but one thing for sure was ...it lost the tail rotor and became a spinning top all the way down.
I respect your views on Choppers... but as my dear old granny used to say..... "each to his own"

When you have a transmission or tail failure, you are no longer flying. It is possible to walk away from a tail-rotor failure crash, but it takes one experienced pilot as in the news copter in the NYC crash you referred to. His helicopter experienced a broken belt in the tail rotor drive. In an airplane, the analog would be losing the tail - no yaw control. And you will crash, as in the American Airlines Flight 587 from JFK on November 12, 2001. But you didn't specify why you would need to glide. When you lose an engine, you just glide to a more or less normal landing. Just like an airplane.

 

[Chuck Young]

Even without a tail rotor??

Yupper, even works without a tail rotor. In fact in many cases I think the loss of tail rotor effectiveness is a reason to auto-rotate.

Physics is a wonderful thing Vinny. smile