Minuteman Missile Background
As the Atlas and Titan missile programs took shape during the late 1950s the Air Force began to realize that its first generation of liquid-fuel ICBMs was of limited use. Owing to the hazards inherent in their caustic, volatile liquid-fuel systems and vulnerability of their radio-inertial guidance systems, the early ICBMs were dangerous to operate, expensive to maintain, and difficult to deploy. The Atlas and Titan silos, for example, had to be oversized to accommodate the complicated propellant-loading system, which included storage tanks, piping, and pumps to handle the hundreds of thousands of pounds of gaseous helium, liquid oxygen, and RP-1, a highly refined form of kerosene. It took 15 minutes to pump 249,000 pounds of propellant aboard the "quick firing" Atlas F. It was dangerous work. Four Atlas silos were destroyed when propellant-loading exercises went awry. Two Titan I silos also met a similar fate.
The problems inherent in liquid-fuel missiles came as no surprise to the Air Force. The WDD and Ramo-Wooldridge had considered using solid-fuel engines for Atlas in 1954, but believed that the large solid-fuel motors would be difficult to cast, would not produce sufficient thrust, and would be difficult to control. The Air Force, however, remained interested in solid-fuel engines. Under the direction of Col. Edward Hall, the WDD's chief of propulsion and later Thor program manager, the Air Force funded research in solid fuels throughout the mid-1950s. By March 1957, Hall and his researchers were convinced that solid fuels could power a new generation of ICBMs.
In the summer of 1957 Hall had a major falling out with the WDD's commanding officer, General Schriever. Temporarily without a job, Hall was given a desk in an unused office and told to study solid-fuel missiles. Hall did much more than study the problem. Working alone, over the course of several months, he designed a family of solid-fuel missiles of tactical, intermediate, and intercontinental range. Hall called his ICBM the Minuteman, and proposed that thousands of the relatively small, low-maintenance missiles could be based in unmanned underground silos and fired at a moment's notice.
Initially WDD, which became the Air Force Ballistic Missile Division (AFBMD) on June 1, 1957, had little interest in Minuteman; it was preoccupied with other projects. The Navy, however, had been keeping close tabs on Hall's work, and it incorporated the Air Force's research into its Polaris program. Based in part on Hall's research, the Navy program improved to such an extent that in the fall of 1957 the Navy proposed developing a ground-based version of Polaris for use by the Air Force. Alarmed by the possibility of the Navy's encroachment, the AFBMD promptly began to reconsider the merits of a solid-fuel ICBM.
In February 1958 Schriever flew Hall to Washington to brief the Secretary of Defense, the Secretary of the Air Force, and SAC commander General Curtis LeMay on the Minuteman concept. In comparison to the Atlas and Titan, Minuteman was a diminutive missile, 53 feet tall and weighing only 65,000 pounds. Hall's plan called for a three-stage missile capable of delivering a l- to 5-megaton warhead at ranges between 1,500 and 6,500 miles. The missiles would be based in widely dispersed unmanned silos, hardened to withstand 200 psi overpressure. The low-maintenance missiles would need minimal ground support equipment, limited field maintenance, and a single two-person launch control facility for every 10 missiles. The solid-fuel engines would give Minuteman a virtually instantaneous launch capability, and because the missiles were to be launched from inside their silos, they would be protected until the moment they took flight. Hall emphatically told his audience that solid-fuel technology was ready now, and he estimated that a force of 1,600 Minuteman missiles could be in place by 1965.
Both the Air Force and DOD leadership were captivated by Hall's presentation. They agreed that the present ICBM program was "less than that achievable and desirable," and within 24 hours of Hall's briefing the Air Force authorized the AFBMD to begin limited R&D on the Minuteman. In July 1958 the AFBMD began component development and selecting contractors. In September 1959 the AFBMD selected Boeing Airplane Company of Seattle, Washington, as the Minuteman assembly and test contractor. Boeing later built the missiles at a huge new plant constructed by the Army Corps of Engineers at Hill AFB, Utah.
Once the Air Force selected its contractors, the Minuteman program took shape rapidly. In February 1961 the first Minuteman test flight, an "all up" test that included all three stages and the guidance system, was a complete success. The Air Force placed the first flight of 10 Minuteman missiles on operational alert in October 1962, just in time for the Cuban Missile Crisis. In the years that followed, hundreds more Minuteman missles were deployed, and by November 1966 SAC's Minuteman I force stood at 800 missiles.