Mather Air Force Base Radar Site
Mather Air Force Base Radar Site (1950-1966) - A Cold War Air Force Radar Station first established in 1950 on Mather Air Force Base near Sacramento in Sacramento County, California. Initially known as Radar Lashup Site L-37 at Mather Air Force Base. Assigned a Permanent ID of P-58 and later a Sage ID of Z-58. Turned over to the FAA in 1966.
History of Mather Air Force Base Radar Site
Established in 1950 and became operational in June 1950 as Mather AFB Lashup Radar Site L-37 manned by the 668th AC&W Squadron. The station initially had both a Ground-Control Intercept (GCI) and early warning mission. The early warning mission involved tracking and identifying all aircraft entering their airspace while the GCI mission involved guiding Air Force interceptors to any identified enemy aircraft. Controllers at the station vectored fighter aircraft at the correct course and speed to intercept enemy aircraft using voice commands via ground-to-air radio. The site became part of the Permanent Radar Network in 1951 and was designated site P-58. Initial equipment included two CPS-6B radar radar sets.
SAGE System Transition
The transition of the manual GCI system to the automated SAGE system began with the installation of the FST-2 coordinate data transmitter and search radar upgrades. The FST-2 equipment digitized the radar returns and transmitted the digital returns to the SAGE direction center. Under the SAGE System, interceptor aircraft were directed to their targets by the direction center computers and controllers, greatly reducing the need for local controllers and equipment at every radar station.
The FST-2 was a very large digital system using vacuum tube technology. Over 6900 vacuum tubes were used in each FST-2 requiring 21 air-conditioned cabinets, 40 tons of air conditioning, 43.5 kva of prime power, and usually a large new addition to the operations building. The FST-2B modification added two more cabinets but with newer solid-state (transistor) technology to process coded responses from aircraft transponders.
SAGE System Operation
The site began operation as a SAGE site on 1 Jul 1960 initially feeding the Beale SAGE Direction Center DC-18. The search radar was upgraded to an FPS-20A with a FPS-6 and a FPS-6B height-finder radars.
In 1961 P-58 became a joint use site (FAA/USAF) and the 668th AC&W Squadron was deactivated. While the FAA assumed maintenance of the radar it seems that the FST-2 and perhaps other specific Air Force equipment was maintained by Detachment 2, 666th Radar Squadron at Mill Valley Air Force Station. In 1965 the FAA told ADC that P-58 was no longer required and ADC scheduled it for closure in FY 1967. ADC ended Air Force activities at the site on 1 Sep 1966. The FAA continued to operate the site reportedly with an FPS-91A radar set data tied to the new post 9/11 JSS System. By the end of 2015 the FAA was reporting that all 82 of the legacy radar sets had been updated to the CARSR equipment.
The physical plant of the site was divided into the main site, a cantonment area and a radio site. The main site housed the operations buildings, the radar towers, and the backup generators. The cantonment area housed the enlisted barracks, the bachelor officer's quarters, the orderly room, the dining hall, the motor pool and other support buildings. A separate Ground to Air Transmitter/Receiver (GATR) radio site housed the radio equipment for directing aircraft intercepts.
FAA Radar site on the former Mather Air Force Base in Sacramento County, California.