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Old 8th May 2019, 01:38
  #5106 (permalink)  
Join Date: May 2010
Location: Boston
Age: 69
Posts: 440
Originally Posted by L39 Guy View Post
...as both crews lost control of the aircraft as they were racing around at an unacceptably high speed.

If the crews had done the Stab Trim Runaway memory checklist, which is for events just like this, they would have disabled MCAS just like the crew of the Lion Air incident did and indeed flew the aircraft for an hour and a half with unreliable airspeed and MCAS just waiting to rear its ugly head.
ET was at ~250 when MCAS dumped in 9 seconds of ND trim which led to sharp speed increase. Even so they were still well under VMO when they disabled all electric trim and were apparently unable to manually trim due to aero loads possibly compounded by lack of training in the unloading technique.

This period is unfortunately not well covered in the prelim report but to say they were 'racing around' does seems a bit harsh.

Other pilots have stated that chopping power would need to be done very carefully given the conditions and altitude.
I am not saying they did not simply miss the 'autothrottle off' step but that only added to problems later on.
MurphyWasRight is offline