skydriller
The accident report is available on-line in French
here.
I don't know if there is an english translation, so... here's my translation of a few bits:
Hypotheses
Overstressing....... "this hypothesis is improbable".
Failure due to previous damage...... "not very probable".
A slight precision here... the overstressing hypothesis is "improbable", while the failure due to previous damage is "très peu probable" in the original French. That's not as strong as "improbable". A good lawyer could be gainfully employed arguing about it. In fact, many probably are....
The hypothesis that failure followed a progressive weakening of the main wing spar is the most probable.
Cause of the accident
The accident was caused by the failure in flight of the right wing.
The gluing and assembly defects found are the determining cause of this failure, through weakening and accelerated ageing of the structures concerned, which lowered their resistance to authorised load factors.
The DR400 is the mainstay of French flying club fleets. A lot of influential people argued against any blame being approtioned to the aircraft, and the arguments are not over yet. But, as I said, it has to be kept in proportion. I still fly DR400's quite happily, and would always choose one in preference to a PA28 - despite the latter's stronger wings!