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Old 21st Apr 2019, 14:31
  #4193 (permalink)  
derjodel
 
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Originally Posted by syseng68k
Haven’t posted here for a while and semi retired now, but also electronics / software engineer, three decades plus including avionics systems exposure. Have read this thread and amazed that such a system with a single point of failure could ever have passed certification, either internally or regulatory. Although the circumstances differ, am reminded of the AF447 episode, where the crew were completely disoriented by the system going awol and dumping the a/c in an unknown state, misleading signals, onto an overloaded crew, who really did not stand a chance. Seems to me yet another example of the gap in the man / machine interface...
AF447 was perfefectly flyable - it was the PF who keept pulling up, making the fatal error. Perhaps the underlying issue is that the frame, when on full thrust and full elevator up, will not drop the nose which would make it clear it was stalled.

Anyways, the MAXes which crashed were not flyable, period. The trim could not have been changed - too much resistance to do it manually and another mcas event if you try electric trim.

Quite different situation, IMO. AF447 had much more time to react (but they burned it and who knows how much altitude they needed to recover). They had lots of energy and flyable plane.
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