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Old 16th Nov 2013, 14:26
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captplaystation
 
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Sonya,

I worked for BM at the time of the accident, and was actually made aware of the accident 1hr after it happened by Sim engineers when I emerged from the Orion/Britannia B737 Sim at EMA during my 737 Conversion course.

I knew both crew members personally, so have taken perhaps even more interest than the average Joe in the accident/investigation.

This accident has been done to death in CRM courses in every airline (and there have been a few) I have passed through.

Difficult to know what new ground/insight you can offer on this one.

A few minor/oft ignored points you may find interesting. The action of disengaging the autothrottle (at that time if I remember correctly the 1st item in the recall items for severe engine damage/fire on the 737-400) had the effect of smoothing the damaged engines operation (as the PMC was no longer fluctuating the fuel flow to try & compensate for the damaged engines inefficiency ) If I remember correctly Boeing subsequently reversed the order in the checklist (as I no longer fly the "Classic" I don't know which order it is done in now)

The vibration was so severe, that reading the vibration maters (particularly from the RHS where they were partly "masked" if on full deflection) robbed the crew of a vital parameter (which they later stated they wouldn't have placed much faith in , as the gauges were somewhat junk in the DC9 which was the Capt's previous type) The levels of vibration probably rendered the value of the other engine instrumentation to "useless", as testified by another crew in one of the 2 similar failures which succeeded this one & precluded the grounding of the type. There were no "warning lights" associated with this failure regime, an omission corrected in the instrumentation of the subsequent 737NG.

The fact that the incident happened more or less directly over EMA conspired against them, as they had no need to demand power from the damaged engine until a very late stage of the approach , an extended routing to some other airport would have shown up the deficiency in the remaining engine much sooner & "may" have given them time to relight the one they had shut down.

Boeing/CFM were allowed to certify the new variant of the CFM56 by ground testing only, even if it was in fact substantially different to previous versions , because it was a"variant" rather than a new engine. The deficiencies inherent in the design (vibration at high altitude) were therefore not identified.

The accident showed up many technical deficiencies in many other inspected aircraft concerning their wiring of fire extinguishing/detection systems (cross wiring etc) as there was at one stage a suspicion (later disproved) that the wrong fire warning may have activated. . . nonetheless it was a slap in the face for Boeings Q.C.

Saddest fact of all, is that, for the sake of a couple of hundred metres of flat undershoot (or a different runway ) they would probably have gotten away with collapsed gear/some back injuries. How they managed to land on a busy motorway without hurting anyone in a vehicle is a miracle.

We should always remember that Kevin & Dave were both affable average ability line-pilots, and despite the very public/personal comments made by BM management & the engineering biased chief investigator, this COULD have (in reality) quite probably happened to a large percentage of us.
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