This thread migh have died, but my five cents anyway...
I saw this accident and thought that LTE was responsible, arising from one of two causes:
1. If the helo was flying at max cont, the flying pilot may have overpitched (for whatever reason), resulting in NR decay. Tired engines may contribute to this situation (i.e. not producing advertised power).
2. The more likely scenario would be an engine failure:
- Resulting in rapid NR decay, which must be responded to by reducing the power requirement on the remaining engine to a sustainable level (i.e. to within OEI contingency limits).
- The only way to do this is to descend and attempt to fly out. If immediate descent is not possible (as was the case in this accident due to the helo orientation to the slope), the NR will decay, and the tail rotor will lose effectiveness - hence the uncommanded right yaw, wobbly hover followed by descent.
The above factors seem to suggest to me that if the helo was hovered left side to the slope (i.e. captain on downslope side), an engine failure could be reacted to by allowing the right yaw to occur, which points the helo downslope, allowing an escape route for descent and acceleration to flyaway speed.
I'd be very interested to get feedback on the above, because if I ever had to do a similar mission, that's what I would brief. Thanks.