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Old 11th Mar 2020, 08:46
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Flightlevel41
 
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From page 15 of the report:
At 5:40:00, the first MCAS nose-down trim occurs for 9s. This was after the autopilot had disconnected after 32s of engagement on the crew's third attempt at engaging the autopilot (was this an appropriate action at this point in time?).
After the MCAS activation, the PF needed 90lbs of force to keep the aircraft from pitching nose down.
At 5:40:14, there was manual electric trim for 2s which brought back the stabiliser from 2.1 units to 2.3 units in a nose up direction.
At 5:40:22, the second MCAS activation took place for 7s, which was interrupted by both pilots applying nose up electric trim for 9s.
So in total, we have 18s of automatic nose down trim, but only 11s of nose up trim in opposition.
At the end of this phase, the stabiliser was at 2.3 units with the crew needing 94lbs of force to keep the jet at a 2.5deg pitch up angle.

Some questions here are:
Why were the crew not using the electric trim more aggresively not only to counter MCAS but also to offload the large amount of pressure needed to hold the control column in a nose up attitude? Because they used electric trim they must have known this wasn't a "true" trim runaway situation and so still had control over the horizontal stabiliser.
Did they rush to cut-out the trim without neutralising the stabiliser first?
Also, did the crew have to answer every ATC call and follow heading instructions with a sick airplane? Could they not have asked to standby in order to reduce potential distractions?

I'm a non-pilot just looking to get some additional perspective here. Perhaps there is some context that has been omitted from the CVR or FDR which would explain the pilot's behaviour. To me the information provided so far makes it seem there were opportunities to save the aircraft that MAY have been missed (again need to wait till the final report to make sure).
None of this is take away from a poor Boeing MCAS design or inappropriate FAA oversight. However, I think too many people make the assumption that a bad MCAS design simply means the pilot's have no means to save the aircraft once uncommanded trim begins.
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