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Old 31st Jul 2012, 15:20
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RetiredF4
 
Join Date: Jun 2009
Location: Germany
Age: 71
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DozyWannabe

HN39 - that's sort-of what I was saying. The threshold was exceeded in a transient sense (due to "G" loading and possibly turbulence), but the aircraft was not in danger of actually approaching stall until the apex of the climb.

The point I was trying to make was that while the warning was caused by exceeding the threshold, the aircraft was not in danger of stalling at that point - I was trying to head off another flight of fancy.
But that is not what BEA is saying. See my bolding.

BEA Final report 1.16.3.2 Analysis of the operation of the stall warning
The activations of the warning picked up by the CVR were identified as occurring at between 2 h 10 min 10.4 and 11.3 and between 2 h 10 min 13 and 13.4. The short duration of activation did not make it possible to detect it from the “Stall warning” parameter, but the FWC 1’s “Master warning” parameters were triggered on one point at this time. However, this warning should have continued until about 2 h 10 min 15.5, and then have been triggered again between 2 h 10 min 17 and 19. The disabling of this warning was probably due to the fact that, between 13.4 and 15.5 and then between 17 and 19, and possibly at other times, the three Mach values were abnormally low (three Pitot probes iced up). The warning triggering threshold then suddenly increased to values of about 10°, much greater than the recorded angles of attack, which led to the warning stopping.
BEA said, it´s neither spurious and it should have lasted longer. The warning threshold increased due to the false low mach (frozen pitots), which made the warning stop. What information do you both have, which contradicts the BEA final report? Do i understand the report wrong?

Last edited by RetiredF4; 31st Jul 2012 at 19:30.
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