Thanks for the clarification. Presumably manual pitch trim overrides auto-trim?
This indeed makes the lack of THS movement all the more mysterious; was it frozen, being incorrectly commanded to the extreme pitch limit as a consequence of multiple AoA detection system failures - or did the crew simply make no attempt to use the manual pitch trim?
Perhaps the CVR will clarify this - does the FDR record manual pitch trim pilot inputs?
Regarding 'stuck' AoA sensors, it is unlikely that the sensors themselves would be made by different companies, even though the computer architecture might be. Thinks of it as 'same mouse, different computer' for a simile.
I've had faulty AoA sensors on another aircraft type; on one occasion we experienced stick-shaker at rotate, but on another occasion the stick pusher operated at 300 ft during a training flapless approach when the stall protection system falsly detected a rapid AoA increase, triggering stall protection way before the critical AoA would have been reached (as it is designed to do).
Last edited by BEagle; 2nd March 2009 at 09:11.