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Old 4th Feb 2014, 13:18
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CONF iture
 
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Originally Posted by PEI_3721
Why didn’t the AP initially disengage with pilot overpower. Normally this is a certification requirement to prevent back-driving the trim, as in this incident.
the efforts to apply a nose-up input by the PF on the control column were insufficient to disconnect the autopilot.
There was no trim back-driving, the AP kept the aircraft on the ILS centrelines and applied a nose-down input on the THS as speed was increasing. Most probably FD were centered.

To me, a more informative call from the relief pilot after the amber warning could have been "NO LAND3" to which the PNF could have confirmed "LAND2" FMA indication and the PF who was visual "CONTACT - CONTINUE"
Not being visual at that time, and following AF procedures, the PF would have called "GO AROUND" and execute it.

Originally Posted by mightyauster
Yes, the yokes are mechanically linked, but there is a "break out" mechanism on the torque tube between them, so it is possible to force the yokes in opposite directions. There are pitch transducers on the bottom of each yoke, so the DFDR will pick up the position of each yoke.
Interesting, it would be nice to see a architecture diagram and also some FDR listing. I have now read you can achieve a split of 8 deg (?) but then what next ?
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