341st Missile Wing LGM - 30 Minuteman Missile Launch Sites This is a list of the LGM - 30 Minuteman missile Missile Alert Facilities and Launch Facilities of the 341st Missile Wing , 20th Air Force , assigned to Malmstrom AFB , Montana . Overview . The 341st Missile Wing was the first United States Air Force LGM - 30 Minuteman ICBM wing . On 15 July 1961 , the 341st was reactivated , and a year later , in late July 1962 , the first LGM - 30A Minuteman I arrived and was placed at the Alpha - 9 launch facility . The 10th SMS accepted its final flight on 28 February 1963 . Two months later , the 12th SMS became 100 percent combat ready . In July , the 490th SMS became fully operational , giving the 341st SMW responsibility for 150 silos . A fourth squadron , the 564th , a former SM - 65D Atlas unit , stood up on 1 April 1966 with the LGM - 30F Minuteman II . Beginning in 1967 , all Minuteman I A and B models were replaced by the Minuteman II . The upgrade was completed by June 1969 . In 1975 , the 564th SMS switched from the Minuteman II to the LGM - 30G Minuteman III model . On 28 September 1991 , President Bush ordered all Minuteman IIs off alert status . This order affected three - quarters of the 200 ICBMs stationed at Malmstrom . From 1992 to 1994 , the Air Force removed 150 Minuteman II missiles from their silos to comply with the pending START I Treaty . The 10th , 12th and 490th silos were upgraded to receive Minuteman III missiles , joining the 50 Minuteman III missiles already on alert status with the 564th In 2007 the 564th SMS ' s 50 silos were retired to reduce operating costs . They were last upgraded in the early 1970s and were considerably different from the newer Minuteman III silos upgraded in the 1990s . With their inactivation , the United States number of ground - based ICBMs was reduced to 450 . Facilities . The Missile Alert Facility ( MAF ) consists of a buried and hardened Launch Control Center ( LCC ) and an above - ground Launch Control Support Building ( LCSB ) . MAFs were formerly known as Launch Control Facilities ( LCFs ) but terminology was changed in 1992 with the inactivation of Strategic Air Command ( SAC ) . In addition , a MAF has a landing pad for helicopters ; a large radio tower ; a large " top hat " HF antenna ; a vehicle garage for security vehicles ; recreational facilities , and one or two sewage lagoons . The entire site , except for the helicopter pad and sewage lagoons are secured with a fence and security personnel . About a dozen airmen and officers are assigned to a MAF . The underground Launch Control Center ( LCC ) contains the command and control equipment for missile operations . It is staffed by the two launch officers who have primary control and responsibility for the 10 underground and hardened Launch Facilities ( LF ) s within its flight which contains the operational missile . Each of the five LCCs also has the ability to command and monitor all 50 LFs within the squadron . The LF is unmanned , except when maintenance and security personnel are needed . A squadron is composed of five flights ; flights are denoted by a letter of the alphabet with the facilities controlled by the flight being designated by a number , 01 through 11 , with 01 being the MAF . Units and locations . 10th Missile Squadron . Activated by Strategic Air Command on 1 August 1961 . Organized on 1 December 1961 12th Missile Squadron . Activated by Strategic Air Command on 22 September 1961 . Organized on 1 March 1962 490th Missile Squadron . Activated by Strategic Air Command on 18 December 1961 . Organized on 1 May 1962 564th Missile Squadron . Activated by Strategic Air Command on 14 December 1965 . Organized on 1 April 1966 . Inactivated on 19 August 2008