Rockville Air Force Station
Rockville Air Force Station (1951-1966) - A Cold War U.S. Air Force Radar Station established during the Korean War. Located near Rockville in Parke County, Indiana. Initially assigned a Permanent ID of P-53 and later a Sage ID of Z-53. Closed in 1966.
Established on 16 Apr 1951 and became operational in May 1952 as Rockville Air Force Station manned by the 782nd Aircraft Control & Warning (AC&W) Squadron.
According to "Searching the Skies" below, the initial equipment included two FPS-10 radars, one perhaps serving as a height-finder and the other serving as a search radar. The available aerial photographs of the site taken in 1953 and 1954 do not appear to show the second FPS-10, at least not mounted on a tower or visibly mounted in a mobile configuration.
Note: Some sources indicate that the FPS-10 search radar was replaced by a CPS-6B but "Searching the Skies" below indicates that the FPS-10s were replaced by two FPS-6s and a FPS-7B. The confusion might stem from the fact that the FPS-10 is a stripped down CPS-6B and the major components all had CPS-6B nomenclature tags. The differences in the CPS-6B and FPS-10 were "only in the number of indicators used, in the absence of B-scan indicators and in the telephone system. The CPS-6 has more indicators, and its telephone system is supplied as part of the equipment." It might be very hard for on-site personnel to know they were dealing with an FPS-10 just by looking at it or even by working on it. See MIL-HDBK-162A below for the full explanation under the FPS-10 section.
The FPS-10 radar(s) were replaced by 1959 with two FPS-6 height-finders and a FPS-7B search set. This configuration (a SAGE qualified long-range search radar and two SAGE qualified height-finders) met the requirements for transition to SAGE System operation.
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 1959 initially feeding the Truax SAGE Direction Center DC-07 on 1 Jun 1959. On 1 Nov 1959, the squadron designation was changed from the 782nd AC&W Squadron to 782nd Radar Squadron (SAGE) indicating the new SAGE System role.
The public announcement of the planned closure of Rockville AFS was made by the Secretary of Defense Robert S. McNamara on 19 Nov 1964 through the Pentagon. The projected closure date was by July 1966. Rockville AFS and the 782nd Radar Squadron (SAGE) were deactivated on 25 Jun 1966.
The physical plant of the site was divided into the main site, a cantonment area, a housing 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. Apart from the main site was a small 9 unit housing area built in 1955 for married personnel.
A separate radio site housed the radio equipment for directing aircraft intercepts. Like most early radar stations, Rockville 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.
After several proposed uses for the facilities fell through, the property was sold to the state of Indiana on 13 Dec 1967 for use as the Rockville Correctional Facility. Some of the former Air Force buildings are still in use although most have been demolished.