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Old 23rd October 2004 | 22:10
  #46 (permalink)  
lomapaseo
 
Joined: Mar 2002
Posts: 4,569
Likes: 1
From: Florida
Oh lets just say a collegue operating that flight said thats what happened
Thanks for that, no doubt the log book contains different words and the interpretation by the investigators will be based on those words the DFDR and the condition of the engine when found.

The events to date have been associated with bangs followed by loss of N1. The historical reports of pilots throughout the total industry associate loss of N1 with rotor seizure, after all that is what they have been taught in the simulator. However in all such cases there was no inflight rotor seizure and the loss of N1 was found to be associate4d with loss of signal for any variety of reasons including rub out of the pickup by a damaged engine.

This is not to say that the rotor may not have been found seized upon landing, however the windmilling forces forces alone have keept it turning in the air.

There is still another possibility and that is that a catastrophic rupture of the engine just ahead of the rear mount that carries the torque loads would result in the engine pivoting about the front ball mount possibly pitching the inlet up into the airstream while the rotors in the engine are spooling down from the failure in the back. This has not happened yet due to an engine caused problem with the exception of a B747 pranging an engine on the runway during landing and leaving the engine on the runway with just the rear mount case still hanging from the pylon.

However, a couple of events with each of the engine models has come very close to severing this load path in the past.

I'll await the DFDR whether it shows a significant rate of drop of N1 or just a loss of signal.

BTW if anybody can confirm what's left on the pylon etc. it will put this event better in context with past history.

Last edited by lomapaseo; 24th October 2004 at 01:30.
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