LGM-30 Minuteman thumb|upright|Minuteman 3 missile launch The advent of solid-propellant gave the three-stage LGM-30 Minuteman ICBM a major advantage over earlier liquid propellant ICBMs. In February 1961, the construction began on Minuteman ICBM test launch facilities at Vandenberg. Silos 394A-1 through A-7 were the first constructed for use by the SAC 394th Strategic Missile Squadron.
LGM-30 Min.uteman thumb|upright|Minuteman 3 missile launch The advent of solid-propellant gave the three-stage LGM-30 Minuteman ICBM a major advantage over earlier .liquid propellant ICBMs In February 1961, the construction began on Minuteman ICBM test launch facilities at Vandenberg. Silos 394A-1 through A-7 were the first constructed for use by the SAC 394th Strategic Missile Squadron