Catastrophic engine failure on Flight UA328

[Twigg]

Out of curiosity, how do you tell the difference post mortem between fatigue and a blunt force pigeon at mach 0.8? I feel like that's the kind of question that decides who has to pay a lot of money.

Incredibly lucky that engine debris fell on land, so recoverable, without any known injuries or related damage.

I'm not far from places where debris was found. I checked the lawn just in case, but didn't find any bits of aerospace-grade unobtanium to play with (Not that I wouldn't have reported it, just horsing around)

 

[berkeman]

Out of curiosity, how do you tell the difference post mortem between fatigue and a blunt force pigeon at mach 0.8?

Pigeon guts/blood?

 

[Twigg]

Ok, I feel a little silly not putting that one together lol. Thanks!

 

[Astronuc]

difference post mortem between fatigue and a blunt force pigeon

Besides bird remains, a fatigue crack has a unique pattern of striations, usually propagating from an inclusion or some internal/surface defect finally reaching a critical crack size and rupture, whereas a catastrophic fraction would not have the striations but a ductile fracture. There would be some plastic deformation of the blade as well. One blade failed near the root, while the blade following in the rotation was struck by the first failed blade and broke about half-length. The second blade would have fractured from impact with the first blade.