689th Radar Squadron The 689th Radar Squadron is an inactive United States Air Force unit . It was last assigned to the 25th Air Division , stationed at Mount Hebo Air Force Station , Oregon . It was inactivated on 30 June 1979 . History . The 689th Radar Squadron ' s long range radars ( LRRs ) were part of the Air Force Semi - Automatic Ground Environment ( SAGE ) computer directed system for air defense . Available Squadron electronic equipment was able to support the detection , identification , and destruction of enemy aircraft . This was accomplished by communications between the SAGE computer at McChord AFB , the radars and communications systems at Mt . Hebo , and airborne fighter - interceptor aircraft such as the supersonic F - 106 Delta Dart jet . Radar systems operated and maintained by the 689th included the FPS - 24 search radar and the FPS - 26A and FPS - 90 height finder radar . The FPS - 24 was housed in a 5 story tall ( 85 ft ) building with two separate transmitters , a receiver , and special receiver equipment to provide counter measures against enemy jamming . In addition , the radar antenna was housed beneath a rigid radome about 145 ft in diameter and 100 ft tall . Three separate radomes were installed in the period from 1962 to 1965 . All three were destroyed by high winds , the last in 1968 . As a result the FPS - 24 was removed and a FPS - 27 search radar requiring a much smaller radome was installed . Both height finder radar antennas were protected by smaller , inflatable radomes . Each height finder radar was installed in its own building . The FPS - 26A radar was later modified beginning in 1967 to an FSS - 7 Sea Launched Ballastic Missile ( SLBM ) detector . All three radar buildings were connected together so that 689th personnel could walk between them and the Operations building and be protected from adverse weather conditions . The 689th Radar Squadron was originally assigned to the SAGE Portland Air Defense Sector ( PoADS ) at Adair Air Force Station , Oregon , a part of the 25th Air Division SAGE at McChord AFB , Washington . Higher headquarters included 4th Air Force ( Hamilton AFB , California ) , and Air Defense Command ( Peterson AFB , Colorado ) . As the northernmost LRR site in PoADS , the 689th was also able to feed its radar data to the Seattle Air Defense Sector ( SeADS ) , another adjacent unit of the 25th Air Division . When the PoADS and SeADS were absorbed into the 25th ADiv , the radars of the 689th and related units were connected to the computers there . In July 1967 , Detachment 2 of the 14th Missile Warning Squadron was activated at Mt Hebo AFS to operate a missile warning radar . Both Squadrons are now inactivated . The Air Force equipment and facilities at Mt Hebo have been removed and the site returned to its natural state . A plaque is virtually all that remains of the radar station . It is dedicated " In Memory Of Those Who Served At Mt . Hebo AFS , Oregon . 689th Radar Sq . , Oct . 1956 - June 1979 . Det . 2 14th MWS July 1967 - Sep . 1980 " . Squadron responsibilities included operation and maintenance of the installed radar and communications equipment , and various support activities including food service , supply , power production , civil engineering , administration , transportation , and personnel services . Available facilities included buildings for the radar and communications equipment , barracks for personnel , family housing , a power plant , dining hall , gym , motor pool , and administrative activities . The Squadron had all the functions and capabilities of a small town .