North Truro Air Force Station
North Truro Air Force Station (1951-1985) - A Cold War Air Force Radar Station first established in 1951 on Cape Cod, Barnstable County, Massachusetts. Named North Truro Air Force Station after the location. Initially assigned a Permanent ID of P-10 and later a Sage ID of Z-10 and finally a JSS ID of J-53. Station decommissioned in 1985 and part turned over to the FAA. Now known as North Truro FAA Radar Site.
Established in 1951 and became operational as North Truro Air Force Station manned by the 762nd 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.
Initial equipment included two CPS-3 transportable search radar.
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 in 1958 initially feeding the Stewart SAGE Direction Center DC-02 at Stewart AFB. The search radar was upgraded to an FPS-7 and FPS-6 height-finders were installed.
North Truro AFS played a significant role in the development of the BackUp Interceptor Control (BUIC) program. The BUIC program came about as budget cuts forced the closure of radar sites and SAGE direction centers. The BUIC concept allowed the BUIC equipped sites to take over the functionality of one or more direction centers should they become inoperative. This capability was to have been achieved by adopting more advanced computer systems and software but it also required each BUIC site to have a full complement of highly trained weapons controllers, a very expensive proposition. At the same time the threat from manned bombers was reduced and the vulnerability of radar sites and direction centers increased. In 1974 all of the BUIC III capability was mothballed except the site at Tyndall AFB, Florida. North Truro was the first BUIC II site activated and first radar station to be designated a BUIC III site. BUIC operations ended at North Truro AFS in 1974.
The FST-2 was probably replaced by February 1973 with a FYQ-47 Common Digitizer. The initial 18-month FYQ-47/49 USAF/FAA replacement program was completed in February of 1973 and the North Truro FYQ-47 would have been in place by then.
North Truro AFS was responsible for the maintenance of three remote unattended gap-filler radar sites. The gap-filler sites were place in locations where the main search radar lacked coverage. These sites sent digitized radar target data directly to a direction center. Maintenance teams were dispatched from North Truro AFS for regularly scheduled maintenance or when fault indicators suggested the site had problems. North Truro was responsible for gap-filler sites at Westboro and Chilmark Massachusetts and the site at Fort Dearborn, New Hampshire.
The physical plant of the site was divided into the main site, a housing area, a radio site and a troposcatter communications site. The main site housed two operations buildings (AC&W & SAGE), the radar towers, the enlisted barracks, the bachelor officer's quarters, the orderly room, the chow hall, the motor pool and the backup generators. Apart from the main site was a small 27 unit housing area for married personnel. A separate radio site housed the radio equipment for directing aircraft intercepts. A troposcatter communications site was used for communications with Texas Tower 2, a radar platform 90 miles out in the Atlantic.
North Truro AFS was decommissioned in a 14 Jun 1985 ceremony at the station. A small part of the property was transferred to the FAA and that now houses their ARSR-4 Radar and is now known as North Truro FAA Radar Site. The remainder of the site, including most of the buildings, was transferred to the National Park Service in 1994 and is now part of the Cape Cod National Seashore.
Part of the Cape Cod National Seashore administered by the National Park Service on Cape Cod, Barnstable County, Massachusetts. Most of the buildings are still standing but closed. Several interpretive signs are located on the site.
Visited: 17 May 2012