Minuteman Missile System
In the late 1950s advances in solid-fuel propellants enabled the Air Force to develop its first solid-fuel ICBM, the Minuteman I (LGM-3OA/B). Formal development began in September 1958, and after an extraordinarily rapid development program, the Air Force put its first ten Minuteman ICBMs on operational alert at Malmstrom AFB, Montana, in October 1962. Deployment proceeded at an equally furious pace, and within 5 years 1,000 of the solid-fuel missiles stood poised in their silos. Twice the Air Force modernized the Minuteman, greatly enhancing its capabilities. It deployed the first Minuteman IIs (LGM-30F) in 1966 and the first Minuteman IIIs (LGM-3OG) in 1971. The Minuteman III was the first ICBM to be fitted with multiple independently targetable reentry vehicles (MIRVs) that enabled a single missile to carry up to three warheads, each aimed at a different target. The Minuteman force remained at 1,000 missiles for most of the Cold War. Although 450 Minuteman IIs were taken off operational alert in 1991, 500 Minuteman IIIs will remain on duty well into the twenty-first century.