This is a copy of a chapter from a US Air Force Academy physics textbook published in 1968, prior to Project Blue Book and the 1970 announcement that the Air Force would no longer take an interest in UFOs. It is an informative and fascinating publication, and shows that not only did the Air Force take an interest, they went about it very intelligently. Too bad that has been lost.
DEPARTMENT OF PHYSICS - USAF CHAPTER XXXIII - UNIDENTIFIED FLYING OBJECTS Edited by:
Major Donald G. Carpenter
Lt. Colonel Edward R. Therkelson
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