Originally Posted by
Owain Glyndwr
rudderrudderrat
OK, I accept the case, but I think the vanes would go to one or other of their mechanical stops not rotate through 180 deg.
That said, refer to my edited version of my previous post where I suggest that the 60 kt inhibition could in fact be maintained as is.
I agree intermittent warnings don't help diagnose the problem, but this only applied to the latter stages after the captain's return to the cockpit. 54 seconds continuous operation is hardly intermittent, although this is not affected by the 60 kts affair.
The problem with human cognition is that it is often not 'logical'. A continuous aural warming can be disregarded as the aural cognitive channel overloads. The cessation of the warning however can have an immediate - what's that just happened' effect. So if the aircraft had sat in deep stall effectively the wrong side of the drag curve with the stall warming sounding the PF and PNF in that situation could well not actually realize the sound was there (as was shown on the infamous wheels up video). The captain however on return to the cockpit would have not been so cognitively overloaded and would have noticed the stall warning.
The advantage of stick shakers is that they are a haptic input (feeling and touch) this cognitive channel does not shut down so fast and as instructors well know a sharp clip around the back of the student's head is often the only way to remove the tunnel vision (attentional tunneling) of an overloaded student.
The effect of cognitive overload seems to be overlooked despite a considerable mass of research demonstrating how it is possible for humans even in relatively low stress exercises to ignore the blindingly obvious. It may even be that the more noise and cavalry charges, flags and flashing lights there are, the more the stressed individual actively disregards them and focuses on the one aspect that they are trying to control. This is when PNF is meant to break in 'haptically' perhaps, but in this case his 'focus' seemed to be recalling the captain.