Sault Sainte Marie Air Force Station

Sault Sainte Marie Air Force Station (ADC ID: P-66, NORAD ID: Z-66) is a closed United States Air Force General Surveillance Radar station. It is located 3.0 mi south-southwest of Sault Sainte Marie, Michigan. It was closed in 1979.

History
In November 1950, the 753d Aircraft Control and Warning Squadron was activated by Air Defense Command at a temporary "Lashup" radar site located at Sault Sainte Marie Airport, to provide radar defense coverage for the area. It was equipped with AN/TPS-1B and 1C radars, the site being designated by ADC as L-21.

In late 1951 Air Defense Command selected Sault Sainte Marie as one of twenty-eight radar stations built as part of the second segment of the permanent radar surveillance network. Prompted by the start of the Korean War, on July 11, 1950, the Secretary of the Air Force asked the Secretary of Defense for approval to expedite construction of the second segment of the permanent network. Receiving the Defense Secretary’s approval on July 21, the Air Force directed the Corps of Engineers to proceed with construction.

On 1 January 1952 the 753d AC&W Squadron began operating AN/FPS-3 and AN/FPS-5 radars at the permanent site, being designated as "P-66" by ADC, and initially the station functioned as a Ground-Control Intercept (GCI) 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. During 1956 the Air Force replaced the AN/FPS-5 with an AN/FPS-6 unit. In 1958 the AN/FPS-3 was replaced by an AN/FPS-20 search radar, and soon received a second height-finder radar, an AN/FPS-6B.

During 1960 Sault Sainte Marie AFS joined the Semi Automatic Ground Environment (SAGE) system, initially feeding data to DC-14 at K. I. Sawyer AFB, Michigan. After joining, the squadron was re-designated as the 753d Radar Squadron (SAGE) on 15 July 1960. 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 1963, the station was switched to the SAGE Data Center DC-06 at Custer AFS, Michigan. In 1963 an AN/FPS-35 search radar replaced the AN/FPS-20A. The AN/FPS-6 was removed in 1963, and the AN/FPS-6B was modified to an AN/FPS-90. On 31 July 1963, the site was redesignated as NORAD ID Z-66. In 1964 an AN/FPS-26A height-finder radar was installed.

In addition to the main facility, Sault Sainte Marie operated the following AN/FPS-18 Gap Filler sites:
 * Grand Marais AFS, MI   (P-66A) 46.5475°N, -86.03639°W
 * Fibre, MI          (P-66B) 46.15694°N, -84.78444°W

Over the years, the equipment at the station was upgraded or modified to improve the efficiency and accuracy of the information gathered by the radars. Sault Sainte Marie AFS came under Tactical Air Command jurisdiction in October 1979 with the inactivation of Aerospace Defense Command and the formation of ADTAC. The 753rd Radar Squadron was inactivated on 30 October 1979 and Sault Sainte Marie Air Force Station was closed. After the station's closure, sections of the AN/FPS-35 radar antenna were sent to Montauk AFS in 1980 to replace corroded sections of the antenna there.

Today the former Air Force Housing site is occupied as private homes. The operational area used as an auto junkyard and other small businesses in the former USAF buildings. The radar towers remain, and the remains of the center section of the large FPS-35 sail lies on the ground where it was apparently dropped when it was removed, the base of the antenna remains on top of the large tower.

Units

 * Constituted as the 753d Aircraft Control and Warning Squadron on 14 November 1950
 * Activated at Sault Sainte Marie Airport on 27 November 1950
 * Site renamed Sault Sainte Marie Air Force Station
 * Redesignated 753d Radar Squadron (SAGE) on 15 July 1960
 * Redesignated 753d Radar Squadron on 1 February 1974
 * Inactivated on 30 October 1979

Assignments:
 * 541st Aircraft Control and Warning Group, 27 November 1950
 * 30th Air Division, 6 February 1952
 * 4706th Defense Wing, 16 February 1953
 * 37th Air Division, 8 July 1956
 * 30th Air Division, 1 April 1959
 * Sault Sainte Marie Air Defense Sector, 1 April 1960
 * Duluth Air Defense Sector, 1 October 1963
 * 29th Air Division, 1 April 1966
 * 34th Air Division, 15 September 1969
 * 29th Air Division, 14 November 1969
 * 23d Air Division, 19 November 1969 - 30 October 1979