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.
“The Advance”35 pages
Read from the scan by GLM-OCR; expect the odd misread word.
Secret NOFORN
Chapter 2
Realizing that the 240-inch lens was both too large and too heavy for the camera bay, Baker scaled the lens down to a 200-inch f/16.0 system. This was still too big. Further reductions followed, resulting by July 1955 in a 120-inch f/10.9 lens that met both the weight and space limitations. Later in the year, Baker decided to make the mirrors for the system out of a new, lightweight foamed silica material developed by Pittsburgh-Corning Glass Company. This reduced the weight significantly, and he was able to scale up the lens to a 180-inch f/13.85 reflective system for a 13- by 13-inch format. In the past, the calculations for such a complex camera lens would have taken years to complete, but thanks to Baker's ray-tracing computer program, he was able to accomplish the task in just 16 days.
When a C camera built by Hycon was flight-tested on 31 January 1957, project engineers discovered that its 180-inch focal length, which was five times longer than that of the B camera, made the camera very sensitive to aircraft vibration and led to great difficulty in aiming the C camera from altitudes above 68,000 feet. The engineers, therefore, decided to shelve the camera. More than five years later, a redesigned C camera was employed during the Cuban Missile Crisis in October 1962, but the results were not very satisfactory.
The failure of the C camera design was not a serious setback to the high-altitude reconnaissance program, because the B camera proved highly successful. Once initial difficulties with the film-transport system were overcome, the B camera became the workhorse of high-altitude photography. An improved version known as the B-2 is still in use. Both of the earlier A-model cameras were phased out after September 1958.
During the period when he was designing lenses for the CIA's overhead reconnaissance program, James Baker was also working on classified lens designs for the Air Force and unclassified designs for the Smithsonian Institution. To protect the security of Baker's work for the Agency, Herbert Miller of the Development Projects Staff told Baker to work on lenses for the U-2 in the open and not make any effort to classify the documents connected with the project. Miller believed that by not calling attention to the effort through the use of special security measures, the project could be completed faster and still not be compromised. This "hiding in the open" strategy proved very successful. $ ^{21} $ Not linked to a story yet.
FOIA release, from the cia-readingroom collection. The PDF is mirrored here; the original link is above. The text was read from the page images by GLM-OCR; expect the odd misread word. 406 pages are in the text index: search them above, or from the library's search.