Documents / Official release
This is a Secret History Staff monograph by Gregory W. Pedlow and Donald E. Welzenbach of the Central Intelligence Agency, published in 1992. It gives a history of the CIA's manned overhead reconnaissance program from 1954 to 1974, covering the development and operation of the U-2 and the A-12 OXCART aircraft. It covers overflights of the Soviet Union, the 1960 downing of Francis Gary Powers, and later operations. One section is titled "U-2s, UFOs, and Operation BLUE BOOK."
From the source:Release of 2026-06-12 This CIA History Staff document chronicles the complete history of the U-2 and OXCART (A-12) high-altitude reconnaissance aircraft programs from 1954 to 1974, detailing their development, operations over the Soviet Union and other targets worldwide, the famous downing of Francis Gary Powers in 1960, organizational reforms following that incident, and the eventual transfer of operations from CIA to Air Force control. A more redacted version of this document has been available on CIA's public website.
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Official release, from the pursue collection. The PDF is mirrored here; the original link is under it. 406 pages are in the text index: search them above, or from the library's search.