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Old 18th Sep 2014, 22:19
  #409 (permalink)  
DozyWannabe
 
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@mm43 - Cheers for the reminder!:

However, (and begging your pardon if I'm mistaken) - in that case you were talking about the behaviour after the stall had developed, whereas here the discussion seems to be centred on the initial right roll immediately after AP disconnect - i.e. when the aircraft was still flying.

[EDIT : Sorry - missed this...]
Originally Posted by _Phoenix_
I just agree with your presumption of overcontrolling, that's normal startle affect at AP disconnection. Watch again the magenta graph after 2:10:10, the next 15 seconds. There is not a roll oscillation, equal quantity left-right. The roll attitude is always much larger on right side
Right, but on the second roll input to the right (02:10:13), he has the stick over a little further for slightly longer than he had it to the left, which could also be another explanation for the right-roll tendency. Additionally, they were in turbulence, which makes detailed correllation of input to response significantly more difficult.

OG's comment regarding the Yaw Trim setting is very interesting, because that may indeed have initially caused a tendency to roll to the right - however (and despite the low resolution of the graph import), it appears that the Yaw Damper might have been compensating towards the left shortly after AP disconnect.

He trusted some instruments that look valid. He followed the FD bars.
Again - that's a possibility, but by no means a certainty.

Why FD didn't step out, as AP disconnected, by design?
It doesn't always, which is why the first memory action in the "safe conduct" Airbus UAS drill:
http://www.bea.aero/docspa/2009/f-cp...nexe.06.en.pdf

is to manually ensure that both AP and FDs are OFF.

Last edited by DozyWannabe; 19th Sep 2014 at 00:23.
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