Originally Posted by
Cubdriver
Counterrotating twins don't stall in vmc demo before reaching vmc as long as the density altitude is high enough. Assymetrical thrust goes down due to the thinner air.
???? This makes no sense at all....
At a LOWER density altitude, the operating engine makes more thrust and will Vmc when airspeed drops enough to use up all the rudder.
At a HIGHER density altitude, the operating engine makes LESS power, so the airplane can get significantly slower before you run out of rudder.
At altitude , many gutless light twins will get slow enough to stall BEFORE running out of rudder (cuz the engine is so weak)...in this case your Vmc demo actually never occurs...you terminate the manuever at the first stall indications. This would happen around 4K-7K MSL, IIRC.
The trick here is that the engine is idle, not feathered, and you recover before the stall really develops. I'm pretty sure this is in the PTS somewhere.