History of Eglin AFB FPS-85, FL
A large AN/FPS-85 phased-array radar was built here starting in 1962. Bendix was the primary contractor. This radar subsequently was rebuilt after a devastating fire in 1965. The replacement unit became operational in 1969 and has since played an important role in tracking orbiting objects and warning against a submarine-launched ballistic missile (SLBM) attack.
References: "Searching the Skies"
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Radar construction began October 1962, at test site C?6, about 35 miles east of Eglin Air Force Base, Fla. The testing was scheduled for May 1965, but four months before, the building and all the equipment were destroyed in a fire caused by arcing electrical equipment.
The Air Force took ownership of the site in September 1968 with the 20th Surveillance Squadron as the primary operator. Initially charged with tracking objects in Earth's orbit, new software installed in 1975 allowed tracking of submarine launched ballistic missiles. This became the unit's primary mission, while continuing to perform space tracking.
The AN/FPS?85 played an active role in America's space program. From 1971 to 1984, the 20th SURS was the site of the Alternate Space Surveillance Center. It provided computational support to the Space Surveillance Center at Cheyenne Mountain AS, Colo. If the need arose, the squadron could assume command and control for worldwide space track sensors.
The 20th SURS was renamed the 20th Missile Warning Squadron in 1979; the 2159th Communications Squadron was added in the same year. In May 1983, the squadron joined Air Force Space Command and became a component of the U.S. Space Command. During this time, the AN/FPS?85 was the proving ground for the Air Force's phased array radars. The new technology was used in new radars specifically designed and located for early warning of SLBM attacks.
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In 1987, the site returned to its original mission?space surveillance. The 2159th Communications Squadron went through a number of transitions and eventually deactivated and incorporated into the 20th MWS. The squadron became the 20th Surveillance Squadron in May 1987.
The site underwent a major transition, allowing Defense Department civilians to staff the majority of support and maintenance functions, while military people staffed the command section, orderly room and operations functions. The unit moved to the 73rd Space Group and was renamed the 20th Space Surveillance Squadron in May 1992. When the 73rd SG inactivated in 1995, the unit was transferred to the 21st Space Wing.
Source: http://www.spacecom.af.mil/21sw/library/fact_sheets/20spss.htm
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