Originally Posted by
MurphyWasRight
One last time: Please look at the ET traces from 05:40:00 (first MCAS) to 05:40:45.
This shows MCAS trimming down, an inadequate pilot retrim followed by another MCAS trim 5 seconds later, this second MCAS trim was interrupted after 6 seconds by pilot trim.
This pilot trim continues until trim cutout. Had they waited 10 more seconds while continuing to apply trim the AC would likely be in trim.
Each of these trim inputs clearly show on the pitch trim trace.
All of the above is exactly as described by original MCAS 'disclosure'.
Not sure where the '3 sec up' in your post comes from, the second pilot trim in above is 8 or 9 seconds (hard to read exactly from graph).
They did re-enable electric trim at end, likely a desperate measure, unfortunately they did not provide sustained trim inputs but did re-trigger MCAS one last time.
The trim position trace at 05:43:15 show a slight upward bump after the 2 'blip' showing the electric trim working against the aero loads.
The trim inputs would not show on the trace if still cutout due to cutout switch wiring.
"One last time" the FDR trace does not track thumb switch trim inputs. Therefore, it cannot be said with certainty what the pilots were doing. The assumption is that Boeing advice is correct but it is not absolutely certain. Unless you can authoritatively show that MCAS has no authority during thumb switch input in all circumstances then you are speculating.