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Old 21st Mar 2019, 18:13
  #2264 (permalink)  
yanrair
 
Join Date: Nov 2007
Location: dublin
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[QUOTE=Tunkurman;10425639]Have you seen this 737 runaway stabilizer training on YouTube? OMG when that stab wheel is running there is not much time to react. Very scary. Look at the first officer trainee's reaction when the warning signals turn on and the plane dips. After seeing this I am so sad to see that these easy to access STAB TRIM switches could have saved both planes.

www.youtube.com/watch?v=3pPRuFHR1co

Thanks Tunkurman. Sort of proves what I have been saying all along. Notice that within 12 seconds the stabiliser is disabled by STAB OFF switches. The runaway STAB drill which is a memory checklist says
Condition "STAB TRIM RUNS CONTINUOUSLY" but if you note in this video, if is off after 12 seconds and before the plane can even begin to become unstable. The guys did not even spill their coffee and the remainder of the flight was very calm.
The word "CONTINUOUSLY" has always meant to me and I am sure thousands of 737 pilots to mean running in a manner not expected because in normal use it just moves in small increments either up or down. The moment it runs for more than a few seconds, that is a runaway.
If we are to start analysing every word in the Boeing QRH for its hidden meaning then the whole thing becomes a farce. During training we are shown that a stabiliser running is a very dangerous situation that needs instant memory action. It is this training that instills the knowledge of how to react - not a single word in a checklist.
There is a difference in the Lion Air in that there may have been stick shaker activity as well but multiple failures are a fact of life when flying and then QRH makes this very clear. "This document does not cover multiple failures.........." which must be dealt with by airmanship. No document could ever cover multiple failures.
Yanrair.


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