Originally Posted by
MechEngr
They were descending. How much thrust would they need? The PM should have been noticing the drop in air speed.
The PF heard the engines making power, just as they had been.
There would have been terrible confusion when the speed loss was noted and adding more power didn't change the speed, but I expect it was too late to scan all the instruments before finally getting to the prop feather levers.
While one might think that would be the first place to look, what would have been the action that would have changed their position that the PF would have based that scan on? At the same time the PF had no doubt been confused by the requirement to ask for the flap setting a second time as that trim change (or lack of it after the first request) would have been noticeable. The PF depended on the experienced PM to do what was agreed upon and not make a horrible screw-up.
As I mentioned earlier - those levers should have a related voice recording overriding every other sound the cockpit can make with "FEATHER 1 FEATHER 2" because the results of unexpected feathering are devastating.
Or maybe there needs to be an extra protection to prevent both condition leavers being moved to feather, at the same time when the plane is airborne. This would make it different from doing it when shutting down the engines, so would require a conscious effort to do it. It should also apply to fuel cut off too when airborne. The issue with aural callouts is I suspect the same as the shape of the lever, the brain will hear what it expects to hear when stress is high, not what is actually said.