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Old 11th September 2011 | 00:54
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DozyWannabe
 
Joined: Jul 2002
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From: UK
Originally Posted by jcjeant
Personnaly I prefer work with what I know ... instead with what I don't know..
Me too (along with most rational people, one would hope!). What I'm saying is that until we know the reasoning behind the logic tree, we need to be careful about making snap decisions over the changes we'd like to see applied. Right now we're talking about a single accident among tens if not hundreds of thousands of safe flights made by the A330 over its service life and the risk is that making a change based on a single incident without properly identifying the potential consquences of that change could make the type less safe rather than more.

Originally Posted by Lyman
Once STALLED, allowing the cessation of the WARNING is inexcusable, by any stretch.
20/20 hindsight is a wonderful thing, but the problem here is that the aircraft was so far outside of the flight envelope by the time the stall warning stopped that the very devices used to calculate the data used for stall warning were considered to be unable to generate reliable data.

Look at the response on here when the initial flight recorder data was released - most pilots were in a state of stunned disbelief that a professional crew could have put the aircraft in that state - it's not a major leap of imagination to suggest that the engineers and designers were equally incredulous both before and after the incident.

Perhaps disabling all but the few critical prompts (and certainly the ECAM) might be a start.
But that's the very reason the systems are designed the way they are - i.e. to logically separate out any spurious warnings. The ECAM tells the pilots what is wrong with the aircraft - what good would disabling that do?

We're in danger of losing sight of the fact that the stall warning operated correctly for some time after the aircraft had departed from it's certified envelope. No amount of fiddling with the logic at the extreme level of the envelope excursion concerned can alter the fact that the warning was not heeded, and right now there's no evidence that any of the crew were distracted by any other noises or displays.

Last edited by DozyWannabe; 11th September 2011 at 01:08.
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