IV. Stanley R. Mickelsen Safeguard Complex
B. Facility Description
4. Missiles
. . . . Short-range interception called for the Sprint missiles. They were to be used for terminal defense (i.e., a concentrated defense against ICBM's that had penetrated the long-range defense or had passed into the atmosphere). These were two stage, solid propellant missiles designed to intercept nuclear reentry vehicles at a relatively close range. They used warheads which contained high energy neutron kill mechanisms, designed to minimize the blast and debris effects in the area of detonation. Sprints were also stored in underground, environmentally controlled cells. Like the Spartans, they could be automatically or manually fired, by launching with a gas propelled piston through an explosively fragmented cell cover. They had several safety features as well. Once the missile was above the cell and airborne, the booster would ignite. Sprints had an extremely high acceleration, reaching their intercept altitude within seconds, and their design included an ablative heat shield to withstand far more heat and pressure than any previous missile. Indeed, their electronic and mechanical components could sustain acceleration loads exceeding 100 g's, and air friction heat to roughly 3,000
o F.