The company’s investigations have led it to the conclusion that no abnormal dynamic overload is present. Instead, Eurocopter’s perspective is that a combination of factors can lead to a weakened fatigue strength of the EC225’s vertical shaft.
A flight test to demonstrate the scenario up to full rupture is currently in progress.
Taking this statement at face value and given the difficulty EC had in replicating the failure if EC can now demo a failure in flight then doesn't it suggest that requires specific actions to do so....which could also be avoided and therefore the shaft won't fail?
OR
We can't predict the initial crack the flight testing is done on one already cracked but not totally failed? And we are testing what exactly?
Which is it??
Either way seems to me the conclusion now can only be either the EC225 has flakey shaft material beyond the material spec change they highlighted as a possible cause initially OR its not being operated as it was intended OR something has changed and wasn't fully tested or understood.
This is an interesting clip, about a month old.
Interestingly across the panel everyone wants to put distance between themselves and a timescale. Not one of the group wants to be tied to remarks on date. They lie (see around minute 27) when they talk about the comments regarding the return to flying in the EC225. The comments attributed were not as Les Linklater suggests to fill column inches. They were comments from a transcripted earnings call. The words were absolutely said. If you want to back track from it later - fine but they were said in context.
You can also see ref to V12 FADEC (15m) and Aberdeen operation (23m), the fact there are no other cracks in the entire EC225 fleet.
Interesting context to see where they were in mid-Feb and how that will relate to 6 weeks later and of course the statements around the return to flying only once the cause is known.