Flight Article WK 24th Feb-2 March
Thumbing through Flight International this morning I came across an article on the Buffalo disaster, page 11.
It was interesting to note that the major focus of the investigation has swung from a severe icing encounter, to one of "a complex chain of events".
I dont become a Q400 driver until later this year, but reviewing the data quoted in the article, the speeds flown and the Vref quoted all seem sensible. As do the configuration changes for the impending landing.
However, the quoted sequence of events following the stick shaker is confusing, maybe a current Q400 driver could clarify.
The stick shaker activated 34s after selection of flap to 15º followed by the stick pusher. Just after the pusher activated, the aircraft pitched UP 31º and the AP disengaged. The crew then selected gear and flap up. The aircraft then entered high rate, left and right roll excursions and pitched 45º nose down. It wasnt until 6s after the upset that the crew applied max power.
Additionally, the crew had activated the icing switch to increment the shaker/pusher speeds by 20kts. I understand this to mean they had a significant buffer between stall warning, and actual aerodynamic stall.