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Old 26th Apr 2019, 14:59
  #4370 (permalink)  
hans brinker
Join Date: Nov 2010
Location: Denver
Age: 53
Posts: 1
Originally Posted by HundredPercentPlease View Post
When I was trained on the 737 (classic and NG), the stab trim runaway was a runaway - where the trim wheel ran continuously. We would identify it as a runaway, because it was continuously running, and flick the switches.

1. MCAS activation is not continuous, it's bursts.
2. The 737 trim system likes to provide bursts of random trim at certain times (STS) so bursts are considered normal.

This is why the Boeing excuse "they should have done the runaway stab QRH to fix the MCAS problem" is a load of utter nonsense. 737 Driver - pinning this on lack of airmanship will costs lives in the future.
I think we disagree where a burst ends and continuously starts. Only been in the jumpseat of the 737, but I would be wildly surprised if STS would ever trim more than a second or two. Having the trim wheel run for ten seconds is way more than a burst. Having said that I can totally see the pilots not realizing what is going on amidst the whole set of stall warning/stick shaker/UAS indications. MCAS should never have been certified using only one AOA at a time, and I feel the same goes for the stall warning/stick shaker, there should at least be an easy way to cancel the alert if the warning is spurious.
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