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Old 18th Nov 2018, 21:47
  #1390 (permalink)  
Concours77
 
Join Date: Nov 2016
Location: Lakeside
Posts: 428
Originally Posted by pax2908 View Post
It "seems: to me (please correct, or ignore, as appropriate) possible that a single sensor failure could trigger both UAS _and_ (pseudo) THS runaway, more or less at the same time. I write "pseudo" because apparently it does not run continuously ... but will come back doing it later ... perhaps making it even more difficult to identify. If true, it is my impression that there should be explicit dedicated training for that particular failure mode.
That’s an interesting catch. If MCAS senses (erroneous) AoA, and pilot catches the “runaway” within the first ten seconds, and starts to wind trim back, when MCAS “stops”, he will crank in unnecessary NU trim, then as MCAS begins a second cycle, well, you get the point, if the pilot is unaware of the function and intermittent cycle, he will chase the trim. FAIL TRIM induced Porpoise! Without specific knowledge of the operation’s cyclic timing, well, don’t try to tame the beast you don’t know.

The fact remains, Boeing gave no chance to the pilot group to “train” the abnormal.



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