Frag Out! Magazine
Issue link: https://fragout.uberflip.com/i/1544638
at a level of 20 MPa. The silos were to be compatible with MINUTEMAN III missiles and next-generation missiles, creating a reliable tool for preemptive or retaliatory nuclear strikes. Despite the assumed high overpressure resistance values, the increasing accuracy of Soviet ICBMs led to the abandonment of the high level of overpressure protection, which was judged inadequate anyway. (As it later turned out, this assessment was not entirely accurate: the Americans overestimated Soviet technical capabilities by roughly eight to ten years.) Another variation on the classic ICBM silo was the Sand Silo. This concept involved placing sealed, elongated containers with ICBMs at the bottom of a shaft approximately 600 m deep, filled with sand. On receipt of a signal from the command post, water was to be pumped under high pressure from a tank located at the bottom of the shaft, liquefying the sand and forcing the missile container upward, thereby enabling launch. The entire system was to withstand a direct hit and a ground burst of up to 5 MT. Approximately 100 silos were planned over an area of 1,000 square miles, underlain by porous rock capable of effectively damping potential shock waves from nearby nuclear impacts. Problematic issues included communications and, above all, the ability to conduct a retaliatory strike after a nuclear attack on the launchers. Potential difficulties were noted in hydrating the sand, whose upper layer could vitrify under the influence of a nuclear blast; interference with the "emergence" of the missile capsules ANALYSIS