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Old 10th Dec 2021, 21:15
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zero/zero
 
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Originally Posted by hec7or
0/0 I admit it doesn't so on second thoughts and according to the graph, the AP was disengaged at the point of GA and not re-engaged until after the altitude was recovered as indicated in Fig 2, but the A/T remained engaged throughout. Looking at the trim inputs, it can be seen that the aircraft descended at the same time the main trim was commanded APND. This coincides with the increase in airspeed and looks like they may have experienced a somatogravic illusion akin to a pitch up.

Clearly if the crew were using main trim, then they knew the AP was not engaged.
I’m not an AAIB investigator and don’t pretend to be, but the nose down trim commands are entirely consistent within the airspeed increasing which is exactly where you’d expect them to be. The graphs don’t tell you how big the trims changes were or whether they were appropriate with the speeds, therefore literally impossible to draw any conclusions.

Last edited by zero/zero; 10th Dec 2021 at 21:33.
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