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Old 28th Apr 2019, 14:01
  #4488 (permalink)  
GordonR_Cape
 
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meleagertoo
Please explain why the current solution should be seen as "bodged" when you already have a speed-trim system (isn't that an electronic 'bodge' too?) that this can ride off the back of, and why it would be 'better' (ie in your terminology somehow less bodged) to add a completely new artificial feel system - despite the fact that MCAS is just that anyway - artificial feel. On the KISS principle MCAS seems remarkably rational to me though as we now know with attendant and unforseen failure modes. I'm far from saying Boeing and the FAA (and by association every other authority that has the MAX on it's register) haven't made errors, but to suggest they are criminal, negligent, collusion or whatever is unfair and irrational without evidence that they are more than mere errors.
I am not a pilot, but from an engineering and computer programming viewpoint, the items listed by BluSdUp (edit: in the other thread) are exactly those I would be concerned about the in the revised MCAS implementation. See: Boeing 737 Max Software Fixes Due to Lion Air Crash Delayed

Any flight control system that relies on an "unreliable" input (AOA disagree threshold of 5.5 degrees), and a 10 second delay lag in implementing nose-down trim, is asking for trouble.

They (collectively) have a much lower probability of killing anyone than the original MCAS, but IMO should never be present on an aircraft that relies on manual flight controls, where precise and direct authority is expected, and pilot/machine induced oscillations could be a killer.

P.S. I have already made the same point several times in this thread (as have some others), and am not going to repeat the whole argument.

Last edited by GordonR_Cape; 28th Apr 2019 at 14:19.
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