Boeing LGM-30A "Minuteman I" ICBM
Propulsion: 1st stage: One Thiokol solid-fuel rocket motor (210,000 lbs thrust);
2nd stage: One Aerojet General solid-fuel rocket motor (60,000 lbs thrust);
3rd stage: One Hercules solid-fuel rocket motor (35,000 lbs thrust)
Diameter: 5 ft 6 in
Length: 53 ft 8 in
Weight: 65,000 lbs (at launch)
Speed: Over 15,000 mph
Range: Over 6,300 miles
Service Ceiling: 7 00 miles
Armament: One nuclear warhead
The Boeing Minuteman was the first ICBM in the world to use solid-fuel rather than liquid-fuel rocket motors, thus it ushered in the second generation of ICBMs. It was smaller and easier to maintain than the first-generation Atlas and Titan ICBMs, and because of its solid propellant could be launched almost instantaneously. Today, almost forty years since the first example became operational, the missile is still the primary ICBM in the nuclear arsenal of the United States.
Research into solid-fueled ICBMs dates back to World War II, but early solid-propellant rocket motors were not sufficiently advanced to allow great success. However, in January 1955, amidst the development of the liquid-fueled Atlas and Titan missile systems, funding was made available for investigation of alternative ICBM designs. The USAF Western Development Division immediately initiated a feasibility study into solid-propellant rocket motors for use on ICBMs and by mid-1957 the secret development of a vehicle called "Missile Q" was underway. The new ICBM would soon become known as the Minuteman.
The Minuteman program was announced to the nation on February 27, 1958 when Congress officially gave the Air Force its approval to begin the research and development of the missile. Seventeen aerospace companies were invited to submit bids for the project, and fourteen responded with design proposals. On October 9, 1958 the Boeing Aircraft Company was selected as the prime contractor on the program.
In April 1959, as the Cold War continued to intensify, the Secretary of Defense ordered the Minuteman program accelerated by one year. The project was assigned "Highest National Priority" by the Department of Defense that September. That same month Boeing launched the first Minuteman mockup at Edwards AFB, California. Test flights of mockup missiles continued into May 1960, all of which were successful.
As development continued on the missile itself, various ideas for basing the Minuteman force were being worked out. In October 1959 the Strategic Air Command announced that a highly mobile basing system using the nation's railroad network was under development. This scheme would make the missiles invulnerable to enemy ICBM attack since they would be constantly moved around the nation on special railroad cars, preventing precise targeting.
A test program called "Project Big Star" was initiated by SAC at the Ogden Air Materiel Area at Hill AFB to determine if the idea would work and in June 1960 the first of four test trains left the base to evaluate the equipment and logistics required to make the concept work. Even though the study proved that the mobile basing idea was feasible, the Defense Department opted for the cheaper alternative of deploying the missiles in dispersed hardened silos spread across the central United States. The mobile Minuteman concept was officially cancelled in December 1961.
On March 25, 1960 the Defense Department authorized the production of 150 SM-80 Minuteman IA ICBMs, to be deployed by mid-1963 in six squadrons. The first successful launch of an SM-80 came on February 1, 1961, but the first attempted silo launch that August failed. The first successful launch of a Minuteman from a silo came on November 17, 1961 and on June 29, 1962 the first launch by an all-USAF crew was executed. The following month the first operational missiles were delivered to the USAF and initial operational capability was achieved on November 30, 1962. The first full Minuteman IA wing in SAC became operational in July 1963.
Since the Minuteman IA had been designed primarily for mobile basing, it was limited in range and firepower compared to the Atlas and Titan ICBMs. Nevertheless, deployment of the 150 missiles continued, with the system being redesignated as the LGM-30A in the summer of 1963.
Each LGM-30A squadron was divided into five flights, each having ten silos and one Launch Control Capsule (LCC). The hardened silos were eighty feet deep and twelve feet in diameter, and could withstand 700 PSI overpressure from nuclear attack. This protected each missile from sabotage and direct enemy attack.
The two-man LCC was buried fifty feet below the surface, protected from up to 1,000 PSI overpressure, and could launch not only its own missiles but those of the rest of the squadron if necessary in wartime. Launching any missile required the turning of two keys simultaneously, the keys being spaced about twelve feet apart on the Launch Console. This was to prevent the firing of a missile by one demented person. Other "fail safe" measures and cross-referenced codes prevented the firing of a missile by two unbalanced individuals.
The improved LGM-30B Minuteman IB began to arrive with USAF units just after the deployment of the LGM-30A was complete. It was designed to provide greater firepower, improved range, and greater targeting flexibility over the Minuteman IA without increasing the size of the missile. The first example went on alert in July 1963 and gradual replacement of the LGM-30A began just over one year later. Deployment of the 650 Minuteman IBs was complete by the summer of 1965, although some Minuteman IAs continued in service until 1969. The LGM-30B served until 1974.
As the Logistics System Program Manager for the nation's entire ICBM force, the Ogden Air Logistics Center at Hill AFB had a close working relationship with all ICBM systems, including the Minuteman family. On 6 January 1959 the base was assigned the management of the SM-80 Minuteman ICBM program. Later that year construction began on Air Force Plant 77 in the West Area of the base. This facility would be owned by the Air Force and operated by Boeing, and would be the final assembly and recycling point for all Minuteman missiles. From here all operational missiles would be delivered to their launch sites by either truck, rail, or air transportation.
In November 1962 the first air shipment of a Minuteman took place when a C-133 transported a missile from Hill to its launching site at Malmstrom AFB, Montana. In January 1963 the first Minuteman missile to be repaired at AF Plant 77 was completed.
In July 1965 the Ogden Air Materiel Area assumed complete logistics management for the entire Minuteman I missile force, all 800 missiles operated by the Strategic Air Command. The following month the first Minuteman II came off the AF Plant 77 assembly line. In January 1966 USAF officials dedicated the $12.5 million Minuteman Missile Engineering Test Facility at Hill, the first and only complete system engineering test facility for an operational missile in the USAF inventory. In June 1967 groundbreaking was held for a new $16.5 million Minuteman II Engineering Test Facility.
On June 26, 1968 the first Minuteman III training missile was shipped from AF Plant 77 to the Boeing Company in Seattle for acceptance testing and check out. This was the lead item in the Minuteman III program. In April 1970 the first operational LGM-30G to be airlifted out of Hill left aboard a C-141. In July 1975 Hill personnel on temporary duty at Malmstrom AFB, Montana, completed installation of the Minuteman III fleet.
Air Force Plant 77 closed on November 30, 1978. As part of the closing ceremonies, representatives of the Air Force accepted the last production Minuteman III missile.
The Minuteman I on display was received from the National Museum of the United States Air Force at Wright-Patterson AFB, Ohio, by the Hill AFB Heritage Program in the summer of 1982. It was moved to Hill Aerospace Museum when it opened in 1987.