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Thread: TOM stall?
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Old 22nd May 2009, 09:18
  #139 (permalink)  
tightcircuit
 
Join Date: Dec 2000
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The problem until recently has been that upset recovery and stall recovery were considered and trained for separately. During set peice stall training we were taught to stop trimming nose up at a certain point rather than trimming all the way to the stall so that the recovery all worked very smoothly with minimum if any height loss etc etc and with no need to trim out of it. There are two clear problems with this. Firstly Mr Boeing forgot to train his autopilots not to trim all the way to the stall. Secondly and more importantly this training completely hid the fact that in any real life accidental stall you were almost certain to be fully trimmed and thus in a position where the standard recovery actions would put you in a jet upset position.

It is of course not just Boeing at fault here. All stall training right from very basic flying training is pretty much the same. The natural reaction to a stall that a pilot develops right from his very first stall detail is full power and adjust the nose attitude (using the elevator not the trim!) to stop the buffet (stick shaker). It is not surprising that this is exactly what this pilot did only to be faced with a rapid pitch up that took him a while to work out how to deal with.

Jet upset or unusual attitude recovery has never received as much attention in the airlines as it clearly deserves. When it happens you need to know what to do instantly ie it needs to be instinctive. Stall training needs to become much more realistic and integrated with upset recovery on a/c types where one can lead to the other.

I crossed with Checkboard whilst writing. I don't disagree with what you say but don't forget you were ready for what was about to happen.

TC

Last edited by tightcircuit; 22nd May 2009 at 12:55.
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