Project Blue Book

Project Blue Book was one of a series of systematic studies of unidentified flying objects (UFOs) conducted by the United States Air Force. It started in 1952, and it was the third study of its kind (the first two were projects Sign (1947) and Grudge (1949)). A termination order was given for the study in December 1969, and all activity under its auspices ceased in January 1970.

Project Blue Book had two goals:

Thousands of UFO reports were collected, analyzed and filed. As the result of the Condon Report (1968), which concluded there was nothing anomalous about UFOs, Project Blue Book was ordered shut down in December 1969 and the Air Force continues to provide the following summary of its investigations:

By the time Project Blue Book ended, it had collected 12,618 UFO reports, and concluded that most of them were misidentifications of natural phenomena (clouds, stars, etc.) or conventional aircraft. According to the National Reconnaissance Office a number of the reports could be explained by flights of the formerly secret reconnaissance planes U-2 and A-12. A small percentage of UFO reports were classified as unexplained, even after stringent analysis. The UFO reports were archived and are available under the Freedom of Information Act, but names and other personal information of all witnesses have been redacted.

Public USAF UFO studies were first initiated under Project Sign at the end of 1947, following many widely publicized UFO reports (see Kenneth Arnold). Project Sign was initiated specifically at the request of General Nathan Twining, chief of the Air Force Materiel Command at Wright-Patterson Air Force Base. Wright-Patterson was also to be the home of Project Sign and all subsequent official USAF public investigations.

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