During the 1950s, the Area 51 base, originally named Watertown Airstrip, consisted of three small hangars, a control tower, dormitories, a warehouse and a few administrative buildings. It was meant to be a temporary facility until all of the U-2 spy planes were deployed to operational sites around the globe.
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Area 51 grew into a permanent facility during the 1960s. New features included large hangars, better personnel accommodations, and an 8,500-foot concrete runway with a 10,000-foot asphalt overrun for emergency use.
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As the base population expanded, several dozen trailers were acquired to provide rudimentary accommodations for contractors, military and government personnel.
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A scale model of the A-12 reconnaissance aircraft was subjected to radar testing atop an inflatable pylon on the west side of the site. Anti-radar coatings and radar-absorbent structures developed during project Oxcart were the forerunners of modern stealth technology.
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In early 1964, nearly the entire fleet of Mach 3 aircraft was lined up on the ramp at Area 51. This included the A-12T trainer, second from right, with its raised instructor's cockpit.
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Workers unload a disassembled U-2 from a C-124 transport. After delivery to Area 51, each airframe was reassembled and prepared for flight-testing.
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Ground crewmen prepare a U-2 for takeoff from the surface of Groom Dry Lake. The lakebed served as a natural airfield, smooth and hard, and capable of supporting the weight of any aircraft.
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Lockheed test pilot Tony LeVier made the initial contractor flights in the U-2 in 1955, ultimately reaching 50,000 feet (more than 20,000 feet shy of design cruise altitude) and achieving the maximum design speed of Mach 0.84.
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U-2 pilots were required to breathe oxygen for two hours -- in order to purge nitrogen bubbles from their bloodstreams -- prior to making a high-altitude flight. Here, Lockheed test pilot Ray Goudey takes this opportunity to catch up on his reading.
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By the late 1980s, the Area 51 base population had grown to the point where a fleet of six Boeing 737s, seen here, was needed to ferry workers in from Burbank, Palmdale and Las Vegas each week.
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Seen head-on, Northrop's Tacit Blue stealth technology demonstrator, now displayed at the National Museum of the U.S. Air Force in Dayton, Ohio, looks like a flying saucer.
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The F-117A was the first operational plane designed to be virtually invisible to radar detection. Its unusual faceted shape gave it an otherworldly appearance.
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Silhouetted against the early morning sky, the unusual shape of the YF-118G Bird of Prey suggests something otherworldly as it soars over the Nevada Test and Training Range.
