LGM-30 Minuteman
The LGM-30 Minuteman is an American land-based intercontinental ballistic missile (ICBM) in service with the Air Force Global Strike Command. As of 2024, the LGM-30G (Version 3)[note 1] is the only land-based ICBM in service in the United States and represents the land leg of the U.S. nuclear triad, along with the Trident II submarine-launched ballistic missile (SLBM) and nuclear weapons carried by long-range strategic bombers.
LGM-30 Minuteman
United States
- About 65,000 lb (29,000 kg) (Minuteman I)
- About 73,000 lb (33,000 kg) (Minuteman II)
- 79,432 lb (36,030 kg) (Minuteman III)[4]
- 53 ft 8 in (16.36 m) (Minuteman I/A)
- 55 ft 11 in (17.04 m) (Minuteman I/B)
- 57 ft 7 in (17.55 m) (Minuteman II)
- 59.9 ft (18.3 m) (Minuteman III)[4]
5 ft 6 in (1.68 m) (1st stage)
Air-burst or contact (surface)
Three-stage solid-fuel rocket engines
- First stage: Thiokol TU-122 (M-55) (178,000 lbf, 790 kN)
- Second stage: Aerojet-General SR-19-AJ-1 (60,181 lbf, 267.70 kN)
- Third stage: Aerojet/Thiokol SR73-AJ/TC-1 (34,170 lbf, 152.0 kN)
First stage 202,600 lb (91,900 kg) (Minuteman III)[4]
700 mi (3,700,000 ft; 1,100 km)[4]
Mach 23
(17,500 miles per hour; 28,200 kilometers per hour; 7.83 kilometers per second) (terminal phase)[4]
Inertial NS-50
Development of the Minuteman began in the mid-1950s when basic research indicated that a solid-fuel rocket motor could stand ready to launch for long periods of time, in contrast to liquid-fueled rockets that required fueling before launch and so might be destroyed in a surprise attack.[10] The missile was named for the colonial minutemen of the American Revolutionary War, who could be ready to fight on short notice.[11][12]
The Minuteman entered service in 1962 as a deterrence weapon that could hit Soviet cities with a second strike and countervalue counterattack if the U.S. was attacked. However, the development of the United States Navy (USN) UGM-27 Polaris, which addressed the same role, allowed the Air Force to modify the Minuteman, boosting its accuracy enough to attack hardened military targets, including Soviet missile silos. The Minuteman II entered service in 1965 with a host of upgrades to improve its accuracy and survivability in the face of an anti-ballistic missile (ABM) system the Soviets were known to be developing. In 1970, the Minuteman III became the first deployed ICBM with multiple independently targetable reentry vehicles (MIRV): three smaller warheads that improved the missile's ability to strike targets defended by ABMs.[13] They were initially armed with the W62 warhead with a yield of 170 kilotons.
By the 1970s, 1,000 Minuteman missiles were deployed. This force has shrunk to 400 Minuteman III missiles as of September 2017,[14] deployed in missile silos around Malmstrom AFB, Montana; Minot AFB, North Dakota; and Francis E. Warren AFB, Wyoming.[15] The Minuteman III will be progressively replaced by the new LGM-35 Sentinel ICBM, to be built by Northrop Grumman,[16] beginning in 2030.[17]
Replacement[edit]
A request for proposal for development and maintenance of a Ground Based Strategic Deterrent (GBSD) next-generation nuclear ICBM, was made by the US Air Force Nuclear Weapons Center, ICBM Systems Directorate, GBSD Division on 29 July 2016. The GBSD would replace MMIII in the land-based portion of the US Nuclear Triad.[71] The new missile to be phased in over a decade from the late 2020s are estimated over a fifty-year life cycle to cost around $86 billion. Boeing, Lockheed Martin, and Northrop Grumman were competing for the contract.[72]
On 21 August 2017, the US Air Force awarded 3-year development contracts to Boeing and Northrop Grumman, for $349 million and $329 million, respectively.[73] One of these companies will be selected to produce this ground-based nuclear ICBM in 2020. In 2027, the GBSD program is expected to enter service and remain active until 2075.[74]
On 14 December 2019, it was announced that Northrop Grumman had won the competition to build the future ICBM. Northrop won by default, as their bid was at the time the only bid left to be considered for the GBSD program (Boeing had dropped out of the bidding contest earlier in 2019). The US Air Force said: "The Air Force will proceed with an aggressive and effective sole-source negotiation." in reference to Northrop's bid.[75]
Preservation[edit]
The Minuteman Missile National Historic Site in South Dakota preserves a Launch Control Facility (D-01) and a launch facility (D-09) under the control of the National Park Service.[76] The North Dakota State Historical Society maintains the Ronald Reagan Minuteman Missile Site, preserving a Missile Alert Facility, Launch Control Center and Launch Facility in the WS-133B "Deuce" configuration, near Cooperstown, North Dakota.[77]