PPRuNe Forums - View Single Post - Interesting note about AA Airbus crash in NYC
Old 30th Dec 2006, 19:27
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DozyWannabe
 
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Originally Posted by RatherBeFlying
If Airbus is that confident of its engineering, why did it not arrange for such a test?
Probably because they were not invited to. In any case, the only precursor for such an event would be the 737 rudder / 727 wake encounter tests that were performed in the lee of the USAir 427 accident. In that case, the 727 was provided by the FAA and the 737 from USAir upon request from the NTSB. The manufacturer (Boeing) was not involved directly in that experiment.
Originally Posted by Scurvy.D.Dog
… Airbus composite fins and rudders in general … or this particular (repaired) fin?
If anything, the only thing that the repair may have changed in this incident is the point at which the vertical stabiliser failed, in this case the rear rather than the front (where the repair was made) - Given the little I know about air resistance and centripetal force, I'd say it would probably have failed where it did regardless of the repair.
what .. damaging a metal fin/rudder (whilst retaining it on the airframe) would give a crew less of more chance of a safe return that the whole thing breaking off?? …
Depends entirely on the failure mode. I believe that it would have made little difference what the rudder was made of if the design was the same, and a similar design has been good enough for the 767 and 777.
I don't think the B52 incident is a fair comparison as the failed vertical stabiliser lay flat over the horizontal and was of a different (split-rudder) design.

Finally, I'd like to repeat the point made in the link I posted, which is it is a crying shame that the incident has caused more response in terms of territorial disputes (pilots/airline vs. manufacturer, US vs. Europe) than it has in terms of co-operation to reduce or eliminate the chance of a similar failure occurring again.

Other aircraft made on both sides of the Atlantic (and Channel for that matter - Concorde was susceptible to partial vertical stab failure, and the vertical stab was built by BAC) have required special handling due to a design feature (the 737 required a faster approach speed while the ECU installed was of original design, for example), and other aircraft have been designed to reduce operating costs by reducing weight. The A320 which offended a certain breed of pilot for potentially endangering their job has no fewer guys in the sharp end than the 737, 757, 767 and 744 - and none of its envelope protection, which supposedly 'wrote the pilot out of the cockpit' prevents evasive maneuvres in an emergency.

In short, blowing hot air based on supposition and pride makes none of us safer and can in fact make things more dangerous, and if proof of that is needed, all we need do is think of the late Captain Stanley Key.

Last edited by DozyWannabe; 30th Dec 2006 at 19:44.
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