Cut Bank Air Force Station
Cut Bank Air Force Station (1951-1965) - A Cold War Air Force Radar Station first established as Del Bonita Air Force Station in 1952 near Cut Bank, Glacier County, Montana. Renamed Cut Bank Air Force Station on 1 Dec 1955. Initially assigned a Permanent ID of P-24 and later a Sage ID of Z-24. Abandoned in 1965.
History of Cut Bank Air Force Station
Established on 1 Dec 1953 as Cut Bank Air Force Station manned by the 681st AC&W Squadron. The station initially had both a Ground-Control Intercept (GCI) and an 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.
In preparation for the transition to the SAGE System, the search radar was upgraded to an FPS-20 and two FPS-6 height-finder radars were installed. This configuration met the standard for SAGE operation of one SAGE qualified search radar and two SAGE qualified height-finders.
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.
The contract for the SAGE annex to the existing operations building was let by the Corps of Engineers to the Lord Carroll Construction Company of Portland Oregon in April 1968 with a stipulated completion time of 180 days. The contract also provided for an addition to the manual side of the operations building and added a total of 3,650 square feet at a contract cost of $140,826. The SAGE Annex to the operations building was completed and the Burroughs FST-2 Coordinate Data Transmitter was installed between October 1959 and February 1960.
SAGE System Operation
The site began operation as a SAGE site on 1 Jul 1960, initially feeding the Malmstrom SAGE Direction Center DC-20 at Malmstrom AFB. The search radar was later upgraded to an FPS-66 and the height-finders were upgraded to one FPS-26 and one FPS-90.
The public announcement of the closure of Cut Bank AFS was given in November 1964 as one of 16 radar sites to be closed across the Nation. At the time of the announcement, Cut Bank was manned by 148 military personnel and 10 civilians. Closing ceremonies were held on 28 Feb 1965. Cut Bank AFS was removed from service as of 1 Mar 1965 and the 681st was deactivated on 25 Jun 1965.
Gap Filler Radars
Cut Bank AFS was responsible for the maintenance of two remote unattended gap-filler radar sites. The unattended gap filler sites were placed in locations where the main search radar lacked coverage. These sites were equipped with short range FPS-14 or FPS-18 search radars and FST-1 Coordinate Data transmitters that sent digitized radar target data to a SAGE direction center and to the main radar site. Both the radar set and the FST-1 were dual channel to increase site up time. Maintenance teams were dispatched for regularly scheduled maintenance or when fault indicators on the FSW-1 remote monitoring equipment suggested the site had problems. The FSW-1 also allowed remote operation of specific functions such as channel changes for the radar and for the FST-1, it also allowed remote operation of the diesel generators at the gap filler site. Cut Bank AFS was responsible for the gap-filler sites at Browning and Sweetgrass Montana.
The physical plant of the main site was divided into an operations area, a cantonment area, and a housing area. The operations area housed the operations building, the radar towers, and the backup generators. The Cantonment Area contained the enlisted barracks, the bachelor officer's quarters, the orderly room, the dining hall, the motor pool, the recreation center, and other support buildings.
Adjacent to the Cantonment Area was a 27 unit housing area for critical married personnel.
A separate radio site housed the radio equipment for directing aircraft intercepts. Like most early radar stations, Miles City originally had a radio transmitter site and a separate radio receiver site used by local controllers for voice direction of fighter interceptors to their targets. With the SAGE System, the SAGE Direction centers had the primary task of directing intercepts and the local radio sites were reconfigured, usually into a single site that was known as the Ground to Air Transmitter Receiver (GATR) site. The GATR site communicated with the interceptors from either the local site or the SAGE direction center via voice commands and/or a digital data link.
Abandoned near Cut Bank, Glacier County, Montana. Some buildings and one tower still standing. The housing area is demolished.