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Old 29th Apr 2019, 08:56
  #4560 (permalink)  
Join Date: Dec 2015
Location: Cape Town, ZA
Age: 58
Posts: 424
Originally Posted by Cows getting bigger View Post
The pilot bit is only one element of the issue. Whichever way you look at this, MCAS was a fix to a problem generated by the manufacturer trying to squeeze the last drop out of an airframe designed before I was born. The fix was, at best, a second rate solution which transferred an additional element of hazard management to the pilots; the expectation was that pilots would be good enough to handle the event. Shuffling risk down the line - hmmmm.

An uninformed question (sorry, only 36 years and 22,000 non-Boeing hrs) - how often has the 737 flavour of aircraft had a trim runaway event, how is it manifested (other warnings/cautions) and at what rate does the trim runaway?
Just my wild speculation, but there are several orders of risk:
1. How many times has runaway trim actually pushed a B737 into the ground? Zero.
2. Electromechanical switches are the most likely component to get stuck in the on position. Given that there are two adjacent thumb switches on the B737, and both have to be active, this seems like an extremely low flight risk.
3. Autopilot software malfunction? Turn off autopilot.
4. Electrical wiring and other faults? Unknown.
5. MCAS? 2 out of 3.
GordonR_Cape is offline