Documents / FOIA release
This is a 1992 CIA History Staff monograph by Gregory W. Pedlow and Donald E. Welzenbach, originally classified Secret NOFORN and approved for release in 2013. It covers the CIA's manned overhead reconnaissance program from 1954 to 1974 and the two aircraft it developed, the U-2 and the A-12 OXCART. The history covers the U-2 overflights of the Soviet Union, the 1960 downing of Francis Gary Powers and later operations in Asia and Latin America. It also includes a section on U-2s, UFOs and Operation BLUE BOOK.
“RAF”18 pages
Secret NOFORN
Chapter 6
First flight of the A-12, 30 April 1962
Initial testing could not explore the A-12's maximum potential, since the J58 engine was still not ready. Developing this power plant to OXCART specifications was proving much more difficult than had been expected because the J58 had to reach performance levels never before achieved by a jet engine, while operating under extremely difficult environmental conditions. To simulate the stress that the J58 would undergo during maximum power output (Mach 3.2 at 97,000 feet), the power plant was tested in the exhaust stream of a J75 engine. In the course of this extremely severe testing, the J58's problems were gradually overcome. By January 1963, Pratt & Whitney had delivered 10 J58 engines to the Nevada testing site. The first flight of an A-12 with two J58 engines took place on 15 January 1963. $ ^{34} $
## SPEED-RELATED PROBLEMS
As J58-equipped A-12s reached higher and higher speeds, more difficulties arose. Major problems developed at speeds between Mach 2.4 and 2.8 because the aircraft's shock wave interfered with the flow of air into the engine, greatly reducing its performance. Solving this problem required long and often highly frustrating experimentation Not linked to a story yet.
FOIA release, from the cia-readingroom collection. The PDF is mirrored here; the original link is under it. The text was read from the page images by an OCR model; expect the odd misread word. 406 pages are in the text index: search them above, or from the library's search.