The BAH Chinook crash was a transmission failure.
JimB,
You failed to catch the point I was making.
The FAA has a definition of "Extremely Remote" as does the DGAC and CAA and JAA and EASA....just to mention a few of the certifying organizations.
My question is how they apply that definition to critical parts and how they determine when to apply the definition to those parts as compared to requiring documented testing of the items.
Look at the Sikorsky situation with the 92 gearbox.....it runs for hours with almost any amount of oil left in the sump....but only minutes with no fluid. It might have run longer if the aircraft had been flown at a reduced power setting than was used. No one anticipated the oil filter failing and causing such a failure as has occurred twice now.
The EC gearboxes have shown themselves to be subject to an unexpected cracking of gears based upon one known event and probably this latest tragedy. Despite HUMS and top notch maintenance engineering we see this failure occur and we now have to question the risk assessment that was applied to the potential failure of the gear box and its critical components.
I am not suggesting we can achieve perfection although that should be the goal otherwise we should not be involved in aviation to begin with.
What we need to do is assess the thinking behind some of the decisons and promises made by the builder and certifying agencies.
In light of this MGB failure at Bond.....the "Extremely Remote" concept just flew out the window!
Bondu,
You posted as I was editing my post.
I feel you prove my point about the definition....if it can happen in the first hour or the last hour....then what does that say about statistical probability.
If we had two failures on the same type aircraft, on the same operation, on the same day.....would that definition still hold? All we would have to do is to have the fleet fly the rest of its service life without a another failure and everything would be okay I guess.