MG, presumably you are talking about a tail rotor control failure (stuck at a fixed pitch), not drive failure (not turning). As you reduce speed the aircraft will yaw RIGHT (but the nose may still be left of your direction of travel), as you lose the streamline effect which helps to counter torque. If it yawed left it is because of the power (torque) reduction, not speed reduction. You are correct in that as you apply power in the hover the nose will want to turn to the right, however if you have a "high power" failure (your terminology), presumably you are describing a scenario where the tail rotor control failed ("stuck") with more pitch than what was required to counter the amount of torque you will pull in the hover, so the nose will still go left, and wind from the right will assist to counter it. Incidentally direction of yaw as you approach does not necessarily tell you which direction the aircraft will turn in the hover as yaw at any stage of your analysis will be affected to varying degrees by your airspeed and torque (and rotor rpm if you can adjust it). Confused?????
[ 23 January 2002: Message edited by: Mark Six ]</p>