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Old 15th Mar 2019, 07:19
  #36 (permalink)  
fdr
 
Join Date: Jun 2001
Location: 3rd Rock, #29B
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It appears that the Max8 still has the STS system incorporated, which is the short period automatic trim at the latter stage of flap retraction. The report states the previous flight was undertaken immediately after a change of the AOA sensor. The indices of the charting do appear to be the same for L and R AOA, so there was an offset at all times when the vane was responding to flow. That looks like an installation issue, the zero is wrong on the L AOA, otherwise the function appears normal.

The prior flight responded correctly to the use of the cutout switches, and the crew at least did use the trim wheel for the rest of the flight, even if there was a continuous stall warning going on in the background. Not a good way to fly.

The MCAS is still a questionable system architecture but the human factor in the handling of this event looks unfortunate. The DFDR for ET302 will be interesting to look at ASAP, as the Max8 may be only part of the problem.
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