We are clutching at straws at this point, but that’s PPrune.
The latest AH paint finishes are water based, good for the environment. Unfortunately they behave like a plastic. In the old days corrosion could reasonably easily be spotted as the paint fell off. Now it’s cocooned in a surface finish that expands to accommodate any change in original profile. Not good for the engineering people, they would literally have to coin tap the surface finish.
A shiney surface finish is a painter’s nightmare.
Back to the plot. Shaft has failed big time, don’t know what I’m talking about but I’d say this incident is head related. Smoking gun probably No 1 sleeve failure due to corrosion/not thick enough in the first place or No 2 damper failure.
But as I said, this is the point where everyone has their 2C worth.