To the point comments on O'Hare UFO from Alfred Lehmberg, on Frank F
Frank Feschino's new book: "SHOOT THEM DOWN"
The Flying Saucer Air Wars of 1952.
This is a book I'ved added to my list; that long list of UFO books. (I'm just now getting to books that came out last year or so.)
I've always maintained that the Flatwoods Monster was probably some sort of military government experimental craft, as well as the Kecksburg UFO event.
(Or maybe the whole thing was due to owls, as chronic skeptic Joe Nickell theorizes.)