LGM-118 Peacekeeper

LGM-118 Peacekeeper
Test launch of a Peacekeeper ICBM by the 1st Strategic Aerospace Division (1 STRAD), Vandenberg AFB, CA (USAF)
TypeIntercontinental ballistic missile
Place of originUnited States
Service history
In serviceDecember 1986 (1986-12)[1] — 12 September 2005 (2005-09-12)[2]
Used byUnited States Air Force
Production history
Manufacturer
Unit costUS$70,000,000 (equivalent to $194,571,949 in 2023)
Specifications
Mass87,750 kg
193,460 lb[3]
Length21.8 m
72 ft[3]
Diameter2.34 m
7.7 ft[3]
WarheadUp to 11 Avco Mk21 re-entry vehicles each carrying a 300 kt W87-0 warhead (though in practice, only 10 were carried); or 12 GE Mk12A re-entry vehicles each carrying a 335–350 kt W78 warhead (never deployed)[4] plus decoys
Detonation
mechanism
Ground-burst and/or air-burst fusing modes

Engine

First stage: 500,000 pounds-force (2.2 MN)
Operational
range
6,000 mi (9,600 km)[5]: 288 [3]-8,700 mi (14,000 km)[6][7]
Maximum speed Approximately 15,000 miles per hour (Mach 20; 24,000 km/h) at burnout[1]
Guidance
system
Inertial (AIRS)
Accuracy130 ft (40 m)[8][9]-300 ft (90 m) CEP[3]
Launch
platform
Fixed silo

The LGM-118 Peacekeeper, originally known as the MX for "Missile, Experimental", was a MIRV-capable intercontinental ballistic missile (ICBM) produced and deployed by the United States from 1985 to 2005. The missile could carry up to eleven Mark 21 reentry vehicles (although treaties limited its actual payload to 10), each armed with a 300-kiloton W87 warhead. Initial plans called for building and deploying 100 MX ICBMs, but budgetary concerns limited the final procurement; only 50 entered service. Disarmament treaties signed after the Peacekeeper's development led to its withdrawal from service in 2005.

Studies on the underlying concept started in the 1960s. The idea was to allow the US to absorb a sneak attack by the USSR with enough warheads surviving to attack the remaining Soviet missile silos. To do so, the missiles had to be highly accurate, be based in such a way that enough would survive a nuclear attack, carry a large number of warheads so the survivors would still inflict massive damage, and be able to rapidly re-target so they could be aimed at only those missiles the Soviets had not yet fired. Over its development through the 1970s, MX emerged as a highly accurate, rapid-firing, and quickly retargeted system. Ultimately, the only problem that was never completely solved was the issue of basing.

Initial development began in 1971, with full-scale development starting in 1974. President Jimmy Carter ordered initial production in 1979 but was overturned by Congress. After considerable debate about the system, in October 1982, President Ronald Reagan announced that 50 of the newly named Peacekeepers would be put into service in existing LGM-30 Minuteman silos, a temporary measure until final basing was decided. The first flight test took place in 1983, which included the successful launch of six inert re-entry vehicles, each hitting pre-planned targets. It was the first US ICBM to use a cold launch system.

Peacekeeper reached initial operational capability in 1986. At this time, the United States and the Soviet Union were negotiating the START II treaty, under which ICBMs were allowed to carry only a single warhead each. Because the Minuteman could carry a single warhead for far less money, the United States agreed to remove the Peacekeeper from their nuclear force in this treaty. Despite the US withdrawal from the Anti-Ballistic Missile Treaty and the subsequent Russian withdrawal from the START II on 14 June 2002, the last Peacekeeper missile was deactivated on 19 September 2005. Their advanced W87 warheads were moved to the Minuteman III.

The private launch firm Orbital Sciences Corporation has developed the Minotaur IV, a four-stage civilian expendable launch system using old Peacekeeper components. As of 2020, seven Minotaur IV flights have been made.

  1. ^ a b Cite error: The named reference FAS_2000 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference Boese_200510 was invoked but never defined (see the help page).
  3. ^ a b c d e Cite error: The named reference MisslieThreat_2021 was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference PalbaCz_2007 was invoked but never defined (see the help page).
  5. ^ Cite error: The named reference Heginbotham_2015 was invoked but never defined (see the help page).
  6. ^ "Peacekeeper Missile". 5 September 2015.
  7. ^ https://www.weapontrend.com/nuclear-weapon-manufacturer-countries/usa/lgm-118-peacekeeper.html [bare URL]
  8. ^ "Peacekeeper Missile". 5 September 2015.
  9. ^ https://www.weapontrend.com/nuclear-weapon-manufacturer-countries/usa/lgm-118-peacekeeper.html [bare URL]