DB
Subject to formal confirmation, I think we can be sure it failed and "fell off" as you say, mercifully just before take-off. As to whys and wherefores, it really would be worth your while trawling through the posts ans siphon out what blakmax in particular has to say about composites and their capacity to fail based on less then perfect production techniques. Supplemented by the observations of some people who've worked on this part of the aircraft, it all makes for very interesting reading.
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