Originally Posted by Chris Scott
Stretching memory back to my pre-Airbus-FBW days on several types, including the A310, I'm sure that it was normal for the AP to use autotrim to combat any yoke displacement by the pilot.
It was "normal" but unwise.
In 94, after Nogoya, Airbus made mandatory the Flight Control Computer modification to allow AP disengagement through manual controls input.
So maybe the failure of the a/c to rotate to a go-around pitch when the PNF pulled hard enough to disconnect the AP was caused purely by the PF's unexplained pushing on the yoke.
This is not what happened. AP disconnected when both were pulling on their yoke.
Only later on the CPT has been unexplainably pushing on his controls.
Detractors of Airbus-FBW should note that, with no AP connection to/from the sidesticks, the action of pulling a sidestick back would have no effect on the AP or autotrim until it was pulled hard enough to disengage the AP. At AP disconnect, the THS would still be trimmed for the vertical profile the AP was last conducting.
Again, nothing here for that 777 indicates that the THS was not trimmed for the vertical profile the AP was last conducting.
Actually, it would be very interesting to know if the too weak action of the CPT on the controls to disconnect AP, had any effect on the THS ... ?
It is a question that Boeing could answer.