general discussion at Sy is that the most likely route was a single engine failure (the Daupin is notorious for poor single-engine performance). The subsequent reduction in Tr rpm (as evident from the high coning angle of the main disc) would cause yaw problems. This (to my mind) could have led to fenestron stall - I don't care what the pundits say, I reckon these devices CAN stall. All the bull!!!! from the AAC years ago about pilot error do not ring true!
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