Originally Posted by
ShyTorque
The recognised "generic" method of dealing with this is to reduce torque and fly away so the fin can have more of an aerodynamic effect (dosen't work so well on some types). If this for some reason has insufficient effect, the only way to regain control is to attempt to get into autorotation. In extremis, the engines might have to be shut down completely.
In the aircraft I have flown, that would be accomplished after one has already reduced the torque/load on the rotor system/entered the auto, if one were in forward flight ... which appears to have been the flight regime this helicopter was in: RTB, in fwd flight. (as far as can be determined).