Originally Posted by pax2908
The conclusion that two of the AoA sensors failed, comes from the fact that the values "do not make sense" at some point in time; and also from the fact that the values are not changing. Of course I don't know, but I presume neither of these clues is taken into account by the system to (in)validate the data? The two wrong AoA values do seem to agree with each other, though. Would the third (supposedly good) data be discarded in such a situation, without any sort of warning?
Very good question !
There is a possibility here that earlier into the flight, due the AOA discrepancy, one of the ADR was rejected by the ELAC, and so
without caution.
Even without automatic ADR rejection, there was numerous opportunities for the system to advise the crew that all AOA readings didn’t agree.
No need to say that a simple hypothetic AOA DISCREPANCY ECAM MSG at this time would have put an early end to the flight test.
Crucial data are missing from the BEA interim report :
- Where is the graph for the third AOA ?
- Where is the graph for the vertical acceleration ?
- Where are the graphs for the FO side stick position ?
- Just too little from the CVR ...
PJ2, I believe SFLY is correct :
25 seconds before the end, the pitch was back in alternate law, but the stabilizer position did not move (?)
There is a possibility that the stabilizer was jammed (?)
There is a possibility that the pilot tried earlier to move it … with no more success than the automatic system (?)