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Old 26th Apr 2019, 02:19
  #4340 (permalink)  
Water pilot
 
Join Date: Mar 2015
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Originally Posted by Brosa
To me it appears that the last crash was a case of "magenta line".

1. Stall warning and stick shaker on rotation
Solution: tried to engage the autopilot at 400 ft

2. Apparantly false stick shaker due to erroneous inputs + unreliable airspeed
Solution: tried to engage the autopilot at 600 ft

3. Still stick shaker due to erroneous inputs from left side
Solution: finally succeeded to engage the left autopilot at 1000 ft

4. Aircraft is grossely out of trim and in an overspeed condition, making it hard to fly
Solution: tried to engage the autopilot
We just don't know their motivation. It had been widely reported in the media and elsewhere that MCAS was only active during manual flight, so a pretty obvious (but unfortunately incorrect) response would have been to turn the autopilot on. If it solved the problem, then a much better solution than dinking around with the manual wheel at low altitude.

Note that in your response, you are assuming that the pilots should have known which side the erroneous inputs came from or that the cause of their troubles was an erroneous AOA gauge. For some reason our brains have a really difficult time with 20/20 hindsight, a fact that is detrimental to human factors design. Almost every problem that I ever solved (and that was a big part of my job) was painfully obvious in hindsight. As I said earlier, my company liked to challenge potential hires with difficult puzzles. I ended up getting into the HR loop and was cursed with a good memory. It was almost funny how my fellow employees would tear down candidates for failing to solve puzzles that I clearly recalled them failing just a few years before...
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