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Saturday, November 28, 2015

Reading List: The Dorian Files Revealed

Outzen, James D., ed. The Dorian Files Revealed. Chantilly, VA: Center for the Study of National Reconnaissance, 2015. ISBN 978-1-937219-18-5.
We often think of the 1960s as a “can do” time, when technological progress, societal self-confidence, and burgeoning economic growth allowed attempting and achieving great things: from landing on the Moon, global communications by satellite, and mass continental and intercontinental transportation by air. But the 1960s were also a time, not just of conflict and the dissolution of the postwar consensus, but also of some grand-scale technological boondoggles and disasters. There was the XB-70 bomber and its companion F-108 fighter plane, the Boeing 2707 supersonic passenger airplane, the NERVA nuclear rocket, the TFX/F-111 swing-wing hangar queen aircraft, and plans for military manned space programs. Each consumed billions of taxpayer dollars with little or nothing to show for the expenditure of money and effort lavished upon them. The present volume, consisting of previously secret information declassified in July 2015, chronicles the history of the Manned Orbiting Laboratory, the U.S. Air Force's second attempt to launch its own astronauts into space to do military tasks there.

The creation of NASA in 1958 took the wind out of the sails of the U.S. military services, who had assumed it would be they who would lead on the road into space and in exploiting space-based assets in the interest of national security. The designation of NASA as a civilian aerospace agency did not preclude military efforts in space, and the Air Force continued with its X-20 Dyna-Soar, a spaceplane intended to be launched on a Titan rocket which would return to Earth and land on a conventional runway. Simultaneous with the cancellation of Dyna-Soar in December 1963, a new military space program, the Manned Orbiting Laboratory (MOL) was announced.

MOL would use a modified version of NASA's Gemini spacecraft to carry two military astronauts into orbit atop a laboratory facility which they could occupy for up to 60 days before returning to Earth in the Gemini capsule. The Gemini and laboratory would be launched by a Titan III booster, requiring only a single launch and no orbital rendezvous or docking to accomplish the mission. The purpose of the program was stated as to “evaluate the utility of manned space flight for military purposes”. This was a cover story or, if you like, a bald-faced lie.

In fact, MOL was a manned spy satellite, intended to produce reconnaissance imagery of targets in the Soviet Union, China, and the communist bloc in the visual, infrared, and radar bands, plus electronic information in much higher resolution than contemporary unmanned spy satellites. Spy satellites operating in the visual spectrum lost on the order of half their images to cloud cover. With a man on board, exposures would be taken only when skies were clear, and images could be compensated for motion of the spacecraft, largely eliminating motion blur. Further, the pilots could scan for “interesting” targets and photograph them as they appeared, and conduct wide-area ocean surveillance.

None of the contemporary drawings showed the internal structure of the MOL, and most people assumed it was a large pressurised structure for various experiments. In fact, most of it was an enormous telescope aimed at the ground, with a 72 inch (1.83 metre) mirror and secondary optics capable of very high resolution photography of targets on the ground. When this document was declassified in 2015, all references to its resolution capability were replaced with statements such as {better than 1 foot}. It is, in fact, a simple geometrical optics calculation to determine that the diffraction-limited resolution of a 1.83 metre mirror in the visual band is around 0.066 arc seconds. In a low orbit suited to imaging in detail, this would yield a resolution of around 4 cm (1.6 inches) as a theoretical maximum. Taking optical imperfections, atmospheric seeing, film resolution, and imperfect motion compensation into account, the actual delivered resolution would be about half this (8 cm, 3.2 inches). Once they state the aperture of the primary mirror, this is easy to work out, so they wasted a lot of black redaction ink in this document. And then, on page 102, they note (not redacted), “During times of crisis the MOL could be transferred from its nominal 80-mile orbit to one of approximately 200–300 miles. In this higher orbit the system would have access to all targets in the Soviet Bloc approximately once every three days and be able to take photographs at resolutions of about one foot.” All right, if they have one foot (12 inch) resolution at 200 miles, then they have 4.8 inch (12 cm) resolution at 80 miles (or, if we take 250 miles altitude, 3.8 inches [9.7 cm]), entirely consistent with my calculation from mirror aperture.

This document is a management, financial, and political history of the MOL program, with relatively little engineering detail. Many of the technological developments of the optical system were later used in unmanned reconnaissance satellite programs and remain secret. What comes across in the sorry history of this program, which, between December 1963 and its cancellation in June of 1969 burned through billions of taxpayer dollars, is that the budgeting, project management, and definition and pursuit of well-defined project goals was just as incompetent as the redaction of technical details discussed in the previous paragraph. There are almost Marx brothers episodes where Florida politicians attempted to keep jobs in their constituencies by blocking launches into polar orbit from Vandenberg Air Force Base while the Air Force could not disclose that polar orbits were essential to overflying targets in the Soviet Union because the reconnaissance mission of MOL was a black program.

Along with this history, a large collection of documents and pictures, all previously secret (and many soporifically boring) has been released. As a publication of the U.S. government, this work is in the public domain.

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