Fortuna Air Force Station

Fortuna Air Force Station
Part of Air Defense Command (ADC)
Elkhorn Township, Divide County, west of Fortuna, North Dakota
Circa 1977 historical photograph
Fortuna AFS Location of Fortuna AFS, North Dakota
Coordinates	48°54′14″N 103°52′00″W / 48.90389°N 103.86667°W / 48.90389; -103.86667 (Fortuna AFS P-27)Coordinates: 48°54′14″N 103°52′00″W / 48.90389°N 103.86667°W / 48.90389; -103.86667 (Fortuna AFS P-27)
Type	Air Force station
Code	ADC ID: P-27 NORAD ID: Z-27
Site information
Owner	sold to civilians, subsequently forfeited to county auditors
Controlled by	United States Air Force
Site history
In use	April 1952–July 1979 (main site), April 1952–1984 (GATR)
Garrison information
Garrison	780th Air Defense Group, 780th Aircraft Control & Warning Squadron (later 780th Radar Squadron)

Fortuna Air Force Station is a closed United States Air Force General Surveillance Radar station. It is located 4.2 miles (6.8 km) west of Fortuna, North Dakota. It was closed in 1979 as a radar station, remaining as a Long-Range Radar (LRR) facility until 1984.

Fortuna Air Force Station was part of the last batch of twenty-three radar stations constructed as part of the Air Defense Command permanent network. It was activated in April, and declared completely operational in late 1952.

The 780th Aircraft Control and Warning Squadron (AC&W Sq) began operations using AN/FPS-3 search and AN/FPS-4 height-finder radars, 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 1957 an AN/GPS-3 search radar made a brief appearance. Reportedly, an AN/TPS-10D was also briefly used. In 1958 the 780th began operating an AN/FPS-20A search radar that replaced the AN/GPS-3. By 1960 a pair of AN/FPS-6, -6A handled height-finder chores.

During 1961 Fortuna AFS joined the Semi Automatic Ground Environment (SAGE) system, initially feeding data to DC-20 at Malmstrom Air Force Base, Montana. After joining, the squadron was redesignated as the 780th Radar Squadron (SAGE) on 1 August 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. Fortuna was incorporated into BUIC I, a manual back-up interceptor control system implemented in 1962. BUIC I provided limited command and control capability in the event the SAGE system was disabled.