Tonopah Air Force Station was initially part of Phase II of the Air Defense Command Mobile Radar program. The Air Force approved this expansion of the Mobile Radar program on October 23, 1952. Radars in this network were designated “SM.” The station became operational on 1 October 1956 when the 866th Aircraft Control and Warning Squadron was moved to the new station, and initially the station functioned as a Ground-Control Intercept and warning station. As a GCI station, the squadron's role was to guide interceptor aircraft toward unidentified intruders picked up on the unit's radar scopes. In 1957 the 866th AC&W Squadron activated an AN/MPS-7 radar and operated manually. In June 1961 the site was moved to another peak and joined the Semi Automatic Ground Environment system, initially feeding data to DC-21 at Stead AFB, Nevada. After joining, the squadron was re-designated as the 866th Radar Squadron on 1 July 1961. The radar squadron provided information 24/7 the SAGE Direction Center where it was analyzed to determine range, direction altitude speed and whether or not aircraft were friendly or hostile. In addition, the 866th Radar Squadron operated a pair of AN/FPS-6 height-finder and AN/FPS-7C search radars. In 1963 the height-finder radars were converted to AN/FPS-90 sets, and on 31 July 1963, the site was redesignated as NORAD ID Z-164. One AN/FPS-90 was retired in 1969. The Air Force inactivated the 866th Radar Squadron 1 July 1970 as a result of budget restrictions, and the general phase down of air defense radar stations. However, during the 1970s, a site near the former radar station was used by the Air Force as part of the Foreign Technology Evaluation program being conducted at nearby Tonopah Test Range Airport. A "Bar Lock" search radar from the Soviet Union was installed at the former Tonopah AFS GATR site to evaluate the Soviet Air Defense System. It was a very valuable tool use for many things. The Air Force needed to develop the all the interfacing equipment in order to use the data in remote locations. Great care was taken not do anything to change the characteristics of the radar itself. A lot of equipment was duplicated and placed in different locations to complete the ground environment, which turned out to be a great training facility. Today, the former Tonopah AFS is now a commercial transmitter site. A few old Air Force buildings are still in use for other uses. The FAA radar uses two out of the three former USAF RADAR platforms.
Air Force units and assignments
Units
Constituted as the 866th Aircraft Control and Warning Squadron
