If you turn off the Engine while in mid air there are no warning sounds (like there were in arma2) and i even tried damaging the helicopter by shooting its tail rotor and disabling it and there are still no warning sounds even while its spinning out of control.

tested in the editor (SP)

i tested it with the follwing helicopters

• ka-60

• ka-60 with weapons

The Littlebirds(MH-9 and AH-9) i couldnt damage the tail rotor without damaging the whole engine.