On Oct 7, 2:33 pm, Tech Support wrote:

I lost a couple of good FACs in VN flying in mountains with a strong
wind. Neither were mountain qualified Pilots.

My WAG is that he probably bought it due to down drafts in strong wind
in mountains.

Will have to see what NTSB comes up with for final analysis.

Even the most experienced mountain pilot can encounter conditions that
are beyond his skill and the aircrafts performance.

Rotor would be my guess