Possible, but pretty unlikely IMO. Bird strikes are something specifically tested for in the early stages of certification. They fire large frozen chickens into an engine running at full speed to make sure the debris stays contained in the engine. They also place explosives on the root of some of the blades during testing to manually separate them, just to make sure everything stays inside the engine. US Airways 1549 ended up in the river because *both* engines got hit by large geese, and a CFM-56 (used on the A320, 737, etc.) is a lot smaller than a PW400. But IIRC, those engines kept the debris inside as designed. If it had been debris on the Denver flight yesterday, it would have happened during takeoff, rather than at 10,000 feet. Birds are still a possibility, but it would have to have been a lot of them to cause an uncontained failure like that (the PW400 is a *large* engine). I'm no engineer, but this seems like fatigue on an older engine that wasn't inspected properly.