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Old 15th Nov 2011, 00:30
  #251 (permalink)  
DozyWannabe
 
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Lyman, if you're going to continue to make such wild extrapolations, I honestly don't see the point.

We know the ADI on the LHS was OK from the DFDR, and the ISIS seems to have been OK too, otherwise the Captain would not have pointed it out. When the Captain comes in, the PF's stick is all the way back and remains so for another 30 seconds, during which time the PF is actually talking to the PNF and the Captain (and at one point tries to extend the speedbrakes). This is a mushing stall and the ADI is varying considerably in pitch and bank as the aircraft tries to get it's nose down (which the PF is almost constantly counteracting). It would appear that they focus on the lateral problems to the exclusion of all else, and the question of pitch doesn't even seem to come into it until they are passing through 10,000ft.

Despite no indications (and a pretty strong counterindication from the stall warning), the PF seems convinced they are in an overspeed situation initially, and following that incorrect intuition consistently applies a recovery technique which is the precise opposite of what he should be doing, unwittingly putting them further and further outside of the flight envelope. By the time the Captain arrives, nothing seems to make sense, but the PF continues to pull.

I'm pretty sure it's not a case of the PF's instruments telling lies, I think that both EFIS and the ISIS were telling the truth, but the truth made no sense to them because nobody asked the right questions. Arguments over yokes aside, the question of "what are you doing?" was never asked, and by the time the PF volunteered the information it was too late.

@jcjeant - Earlier in the sequence, the PNF seems to have a better handle on things (and it's a reasonable assumption that his anxiety for the Captain to return is related to that - he's not happy with the performance of the guy the Captain implicitly put in charge). By the time the exchange where the PF says he's been pulling up for some time happens, confusion seems to have overtaken all three crewmembers.

Last edited by DozyWannabe; 15th Nov 2011 at 00:55.
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