Originally Posted by PT6Driver View Post
Cpn Bloggs
My question on yoke v sidestick was referring to the fact that inappropriate stall recovery is common to all.
Regarding actual handling time of the PF I quite agree with you.
b1lanc:
It wasn't just inappropriate stall recovery. It appears that neither PF recognized they were in a stall even with the stall warnings blaring. That screams for change and not just training or SOP.
I agree, again like in AF 447 it looks like none did recognize the stall situation, at least not in the first vital minute. Imho there is a reason I mentioned in the AF447 thread before. In training only stall approaches and the recovery from those are practiced, not a developped stall. The Nz felt (or simulated in the box) during such a training exercise is 1, transitioning to a bit less than 1 when the descent rate due to stall starts, where recovery is initiated by pushing the nose down. In case where the recovery is started later, the box will neither simulate the true stall behaviur nor the continuous reduced Nz value.
The below 1 reduced Nz is accordingly asociated with the end of the stalled situation and the point where soon after the recovery to level flight starts. If we could check the Nz graph (i could not find it in the report, but forgive me if it is there and I just oferlooked it) we would see similar Nz value like in AF447, the Nz value below 1 ( I gestimate around .7-.9) for a prolonged period of the stalled descent. Such values can be felt very well. They may be even very uncomfortable if they have never been encountered before. Stalls on the other hand are thought to be accompanied by some violent maneuvering of the aircraft asociated with positive Nz. Reduced Nz could therefore be asociated with a unstalled situation.
What is my point? If the flight behaviour prior stall has been missed as being prone for an impending stall, the entry into stall and the following developped stall might be missed completely due to the unspectacular entry, and the felt Nz below 1 could be interpreted as the normalisation of the situation. We know that it is wrong to go after the body sensation, but in a stress situation it will happen anyway.
The most important point for the prevention of a stall and for a necessary stall recovery is the early recognition, that the flight before the stall entry is critical and a stall may occur. Then the crew is prepared for the flight dynamics which could developp during stall entry and also during a developped stall and how ro counter those. The importance lies in the avoidance of such situations.
It is a training issue, imho still not adressed thoroughly enough.