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.
“US Navy”15 pages
Secret NOFORN
power-to-weight ratio of 2.7:1 was almost 20 percent less efficient than the preferred P-31 version. $ ^{40} $
To conduct lengthy missions over hostile territory, the U-2 needed to carry a large amount of fuel. Kelly Johnson used a "wet-wing" design for the U-2, which meant that fuel was not stored in separate fuel tanks but rather in the wing itself. Each wing was divided into two leak-proof compartments, and fuel was pumped into all the cavities within these areas; only the outer 6 feet of the wings were not used for fuel storage. The U-2 also had a 100-gallon reserve tank in its nose. Later, in 1957, Johnson increased the fuel capacity of the U-2 by adding 100-gallon "slipper" tanks under each wing, projecting slightly ahead of the leading edge.
One of the most important considerations in the U-2's fuel system was the need to maintain aircraft trim as the fuel was consumed. The aircraft therefore contained a complex system of feed lines and valves draining to a central sump, which made it impossible to provide the pilot with an empty/full type of fuel gauge. None of the first 50 U-2s had normal fuel gauges. Instead there were mechanical fuel totalizer/counters. Before the start of a mission, the ground crew set the counters to indicate the total amount of fuel in the wings, and then a flow meter subtracted the gallons of fuel actually consumed during the flight. The pilot kept a log of the fuel consumption shown by the counters and compared it with estimates made by mission planners for each leg of the flight. As a double check, U-2 pilots also kept track of their fuel consumption by monitoring airspeed and time in the air. Most pilots became quite expert at this. Several who did not came up short of their home base during the 20 years these planes were flown.41
## INITIAL TESTING OF THE U-2
Preliminary taxi trials began on 27 July 1955, when the first run down the newly completed runway took the plane to 50 knots. Lockheed's chief test pilot, Tony LeVier, was at the controls. A second taxi trial 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.