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Old 4th Apr 2019, 11:09
  #3075 (permalink)  
Join Date: Feb 2011
Location: Grand Turk
Age: 57
Posts: 66
Originally Posted by gmx View Post
It's a reasonable point. However, after the LionAir investigation, everyone knew the electric trim could be used to neutralize MCAS, even if temporarily (as the accident crew had done 20-odd times on the disaster flight). Having MCAS run the trim to its maximum nose down position, and being fully aware of the LionAir situation, wouldn't it make sense to re-trim the aircraft to neutral attitude *before* hitting the cutout switches? Having said that, the pilots have clearly encountered a terrifying circumstance. The only thing you might hope is that after the LionAir incident they were better equipped to deal with it than what seems to have been the case.
It is not known that the pickle switches are the solution. It is just a theory. Of course, that theory could be correct but would not address runaway trim unrelated to MCAS. It is not clear that the testing and simulation has been sufficiently close to the real world situation, particularly if there is very little altitude to play with. Does electric trim beat MCAS within the time frame required? It will require detailed investigation and simulation. It will also have to established whether an average pilot could be expected to recover the aircraft.

I have many questions about the control systems in the MAX series that will only be answered by detailed investigation. It is still possible that the best crew could not have recovered. I think that some of the criticism of the pilots has been unfortunate and premature. It may be likely that crew could have done more, but that does not excuse Boeing for having put them in the situation in the first place. No pilot should be placed in the position that an unreliable safety system is trying to crash the aircraft and it is unclear how to recover or even promptly diagnose precisely what is happening. Boeing's response to the LionAir accident was inadequate in my opinion and the LionAir accident report, thus far, was also insufficient to address all of the issues that were apparent. I suspect that politics has interfered and dumbed down safety concerns.
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