90th 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 90th Missile Wing , 20th Air Force , assigned to Francis E . Warren AFB , Wyoming . Overview . The 90th Strategic Missile Wing was the fifth United States Air Force LGM - 30 Minuteman ICBM wing , the fourth with the LGM - 30B Minuteman I . In October 1962 construction began over an area of Wyoming , Nebraska , and Colorado to construct 200 Minuteman Intercontinental Ballistic Missile launch silos . On 1 July 1963 , the Air Force activated the 90th SMW Over the next year , four component strategic missile squadrons activated 200 minuteman missiles . In November 1972 , SAC initiated the Minuteman Integrated Improvement Program . The program entailed silo hardening and upgrading command data buffers , which allowed for quicker missile retargeting . In addition to receiving upgraded silos and launcher control facilities , Warren also received new missiles , with the Minuteman I being replaced with LGM - 30G Minuteman III between 1973 - 1975 . In November 1982 , in a decision statement for Congress , President Ronald Reagan stated his plan to deploy the MX missile ( later designated the LGM - 118 Peacekeeper ) to superhardened silos located at Warren . In July 1984 , construction began for Peacekeeper support facilities at Warren . From 1986 through 1988 , 50 Peacekeepers were backfitted into silos formally occupied by Minuteman IIIs of the 400th Strategic Missile Squadron . The 400th achieved initial operational capability with 10 deployed Peacekeepers in December 1986 . Full operational capability was achieved in December 1988 with 50 missiles . All of the 90th Wing ' s Minuteman III missiles were reduced from three warheads to a single warhead by START I between 1991 - 2001 . Beginning in 2002 the Peacekeepers began to be inactivated for budgetary reasons , and by September 2005 the 400th SMS was inactivated . The three active Minuteman III squadrons are commanded by the 90th Operations Group . Facilities . The Missile Alert Facility ( MAF ) consists of a buried and hardened Launch Control Facility ( 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 LCC 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 . 319th Missile Squadron . Activated by Strategic Air Command on 24 May 1963 . Organized on 1 October 1963 320th Missile Squadron . Activated by Strategic Air Command on 24 May 1963 . Organized on 8 January 1964 321st Missile Squadron . Activated by Strategic Air Command on 24 May 1963 . Organized on 9 April 1964 400th Missile Squadron . Activated by Strategic Air Command on 10 December 1963 . Organized on 1 July 1964 . Initially equipped with LGM - 30B Minuteman Is . With the deployment of the LGM - 118A Peacekeeper in 1987 , the squadron ' s 50 Minuteman silos ( Flights P through T ) were converted to the Peacekeeper for operational duty . The Peacekeepers were retired between October 2002 and September 2005 , and the squadron was formally inactivated on 19 September .