James, what COULD happen, that a train could hit a UFO? I won't even go into that foolish peculiarity, but having some dents and broken windows on a unit are a long way from saying that it hit a UFO.
Further...I've seen or heard many instances where a shop found damage to a unit, whether visual or not, and had no idea either how it happened or how it COULD have happened. In no way am I disparaging shop forces. It's more like a father wandering out to a car after his son drove it and finding sand all over the inside of the car, and wondering how in the hell it got there, when they don't live anywhere near a beach. (Um, this happened to me...I was the son...)
Last thing: I believe in UFO's, to an extent, and I used to love to read Charles Berlitz' book on the Bermuda Triangle. I'm down with the idea, but methinks you are looking too hard at this stuff.
Dave Becker