Yaak Air Force Station

 (1951-1960) - A Cold War Air Force Radar Station first established in 1951 near Yaak, Lincoln County, Montana. Named Yaak Air Force Station after the location. Initially assigned a Permanent ID of P-11. Briefly became an unmanned gap-filler site in 1960 with an ID of SM-151E and closed in 1960.

History
Established 1 Mar 1951 and operational in April 1952 as Yaak Air Force Station manned by the 680th 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 an FPS-3 search radar and an FPS-4 height-finder radar. An FPS-6 height-finder was installed in 1956. The FPS-4 was replaced by a GPS-3 in 1957.

Gap Fillers
Yaak AFS was responsible for the maintenance of three remote unattended gap-filler radar sites. The gap-filler sites were placed in locations where the main search radar lacked coverage. These sites sent digitized radar target data directly to the main site and to a direction center. Maintenance teams were dispatched from Yaak AFS for regularly scheduled maintenance or when fault indicators suggested the site had problems. The three gap-filler sites were located at Porthill Idaho, Eureka Montana and Moyie Springs Idaho.

Physical Plant
The physical plant of the site was divided into an upper site, a cantonment area, and a radio site. The upper site on Hensley Hill housed the operations building, the radar towers, and generators. The cantonment site included three enlisted barracks, two bachelor officer's quarters, orderly room, dining hall, motor pool, base exchange (BX), emergency power plant and a steam plant. A separate radio site housed the radio equipment for directing aircraft intercepts.

Yaak AFS was considered a remote isolated tour of duty and was theoretically a one-year unaccompanied tour site and no base housing was supplied for married personnel. Married personnel who brought their families with them had to find quarters off base until 1 Nov 1956 when a small 24 pad trailer park was opened for married personnel with their families. The trailers were not furnished by the government.

Closure
Yaak AFS and the 680th AC&W Squadron were deactivated on 1 Jul 1960.

Current Status
Abandoned and demolished.

See Also:
 * SAGE System
 * Permanent System Radar Sites
 * US Radar Sets
 * Geiger Manual Direction Center SM-172
 * McChord Manual Direction Center P-4
 * Malmstrom Manual Direction Center P-83

Sources:
 * , page 160.
 * , page 130.

Links:
 * Wikipedia - Yaak Air Force Station
 * Radomes - Yaak Air Force Station