Peacekeeper Credit - via Andreas Parsch

4 stages, range: 7000+ mi., warhead: nuclear MIRVs warhead: nuclear MIRVs

Historical Essay © Andreas Parsch

Martin Marietta LGM-118 Peacekeeper

The Peacekeeper (originally known as "MX" missile) is the newest ICBM in the USAF inventory. It was intended as a replacement for the LGM-30 Minuteman, but it suffered from a long development time, and will actually be retired before the Minuteman because of arms reduction treaties.

As early as 1966, the USAF made plans to develop an Advanced ICBM (AICBM) including a mobile basing system. AICBM was known as Weapon System 120A, but development was not approved by the Secretary of Defense. Research on a new ICBM did not begin again until November 1971, and in April 1972, the USAF announced a new ICBM program, then known as Missile-X (MX). The initial studies researched all kinds of missiles and basing schemes, including air-launch from modified transport aircraft. The Air Force was always intending to deploy a mobile ICBM, but to avoid unnecessary delays, it was finally decided to design a large solid-fueled missile which would initially be launched from existing Minuteman silos. At a later date, a mobile basing system would be developed. In 1977 the basic design for the MX was finalized. It was to become a four-stage missile, using some advanced technologies, like a "cold launch" capability, in which the missile would be ejected from the launch silo by a gas jet before igniting its first stage motor. This would greatly reduce the damage to the silo, reducing the silo rearming effort to a few days by three men (compared to 17 days by 20 men for a Minuteman silo). However, the U.S. Congress was not pleased with the idea of using Minuteman silos (regarded as too vulnerable), and halted MX development for one year to give the USAF time to select a mobile basing system. Nevertheless, in April and May 1978, Martin Marietta was awarded the prime contract for the MX missile, and Thiokol, Aerojet, Hercules, and Rocketdyne received contracts for the 1st, 2nd, 3rd, and 4th stage engine, respectively.

By 1979, the USAF had decided to employ the MPS (Mobile Protective Shelters) plan, in which 200 MX missiles would be shuttled around between 4600 soft shelters. With the placement of dummy missiles in the unused shelters, the Soviet Union wouldn't know where the real missiles would be at any given time, and theoretically would have to attack every shelter to destroy every missile for sure. The alternate "Racetrack" plan, which was to base the missile on railways on huge underground track networks, was dropped. The MPS was approved in September 1979, and full-scale development of the MX began. At that time, the designation MGM-118A was allocated to the MX missile. Initial development was quick, and by January 1982, all major components, including all rocket stages and the cold launch method had been separately tested.

However, because of very high estimated costs, the MPS was cancelled in 1980, and by 1982, Peacekeeper (the name having been assigned in November 1982) was again close to cancellation because of the lack of a mobile basing system. In early 1983, it was finally decided to base Peacekeeper in Minuteman silos, and to develop a small mobile ICBM at a later time (this was to become the MGM-134 Midgetman, which was eventually cancelled, too). Because the missile was no longer planned to be mobile, the designation was changed to LGM-118A. In June 1983, the first full Peacekeeper launch from a launch canister occurred. After more test launches in the following years, the first few LGM-118A missiles became operational in modified Minuteman silos in December 1986. Peacekeeper deployment was complete in December 1988, when 50 LGM-118As were in silos.

The LGM-118A uses a warhead section with 10 MK.21 reentry vehicles, each carrying a 300 kT W-87 thermonuclear warhead. The missile is guided by an Inertial Reference Sphere navigation system by Rockwell Autonetics, and is more accurate than any previous ICBM, reaching 120 m (400 ft) CEP. When stored in its launching canister and launched by the high-pressure gas jet, the missile is separated from the canister walls by many small "adaptors" mounted to the side of the missile. When the canister is cleared, these adaptors fall away, giving the characteristic picture of a Peacekeeper launch.

In 1986, the so-called "Peacekeeper Rail Garrison" plan was approved. In this scheme, 50 additional Peacekeeper missiles would be based on 25 special USAF trains, with each train consisting of two missile cars, two locomotives, and additional cars for launch control, security, and fuel. The designation MGM-118A was again allocated to these mobile missiles, but the whole plan was cancelled in 1991 after the end of the Cold War.

With the signing of the Strategic Arms Reduction Treaty (START) II in January 1993, Peacekeeper became a dead program. START II demanded the removal of all MIRV ICBMs, and it is currently planned to phase out all LGM-118A missiles until 2004. After that date, the LGM-30 Minuteman will remain the only U.S. land-based ICBM. When production was completed, about 100 LGM-118A missiles had been built.

Note: Data given by several sources show slight variations. Figures given below may therefore be inaccurate!

Data for LGM-118A:

[1] James N. Gibson: "Nuclear Weapons of the United States", Schiffer Publishing Ltd, 1996
[2] Bill Gunston: "The Illustrated Encyclopedia of Rockets and Missiles", Salamander Books Ltd, 1979

Manufacturer: Martin Marietta. Guidance contractor: Boeing. Launches: 51. Failures: 1. Success Rate: 98.04%. First Launch Date: 1983-06-17. Last Launch Date: 2004-07-21. Launch data is: continuing. Apogee: 1,000 km (600 mi). Liftoff Thrust: 1,711.000 kN (384,648 lbf). Total Mass: 88,430 kg (194,950 lb). Core Diameter: 2.34 m (7.67 ft). Total Length: 21.60 m (70.80 ft). Span: 2.34 m (7.67 ft). Standard warhead mass: 3,600 kg (7,900 lb). Maximum range: 13,000 km (8,000 mi). Number Standard Warheads: 10. Standard RV: Mk. 12A. Standard warhead: W87. Standard warhead yield: 300 KT. Boost Propulsion: Solid rocket. Cruise Propulsion: Solid rocket. Guidance: Inertial. Development Cost $: 10,926.800 million. in: 1982 average dollars. Recurring Price $: 77.877 million. Total Number Built: 226. Flyaway Unit Cost $: 77.398 million. in: 1982 unit dollars.

1983 June 17 - Launch Site: Vandenberg. Launch Complex: TP-01. Launch Vehicle: Peacekeeper. LV Configuration: Peacekeeper FTM-1.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Test mission Nation: USA. Agency: USAF AFSC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF SAC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF SAC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF SAC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF SAC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF SAC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF SAC. Apogee: 1,000 km (600 mi). References: 1836.

• Operational Test mission Nation: USA. Agency: USAF SAC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF SAC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF ACC. Apogee: 1,000 km (600 mi). References: 991.

• Operational Test mission Nation: USA. Agency: USAF ACC. Apogee: 1,000 km (600 mi). References: 1836.

• Operational Test mission Nation: USA. Agency: USAF ACC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF AFSPC. Apogee: 1,000 km (600 mi). References: 1812.

• Operational Test mission Nation: USA. Agency: USAF AFSPC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF AFSPC. Apogee: 1,000 km (600 mi). References: 1812.

• Operational Test mission Nation: USA. Agency: USAF AFSPC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF AFSPC. Apogee: 1,000 km (600 mi). References: 1008.

• Operational Test mission Nation: USA. Agency: USAF AFSPC. Apogee: 1,000 km (600 mi). References: 1812.

• Operational Test mission Nation: USA. Agency: USAF AFSPC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF AFSPC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF AFSPC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF AFSPC. Apogee: 1,000 km (600 mi). References: 916.

• Operational Test mission Nation: USA. Agency: USAF AFSPC. Apogee: 1,000 km (600 mi). References: 1812.

• Operational Test mission Nation: USA. Agency: USAF AFSPC. Apogee: 1,000 km (600 mi). References: 1903.

• 9 RVs operational test launch Nation: USA. Agency: USAF AFSPC. Apogee: 1,000 km (600 mi). References: 1903.

• 7 RVs operational test launch Nation: USA. Agency: USAF 90SW. Apogee: 1,000 km (600 mi). References: 1823.

• 8 RVs operational test launch Nation: USA. Agency: USAF 90SW. Apogee: 1,000 km (600 mi). References: 1823.

• 8 RVs operational test launch Nation: USA. Agency: USAF 90SW. Apogee: 1,000 km (600 mi). References: 1912.

• 8 RVs operational test launch Nation: USA. Agency: USAF 90SW. Apogee: 1,000 km (600 mi). References: 1912.

• 8 RVs operational test launch Nation: USA. Agency: USAF 576FTS. Apogee: 1,000 km (600 mi). References: 1912.

• 9 RVs Functional Dependency gate operational test launch Nation: USA. Agency: USAF. Apogee: 100 km (60 mi). FDEP. The Peackeeper ICBM was destroyed during flight and did not reach its planned 1000 km apogee. References: 1912.

• GT-31PA - 9 RVs Functional Dependency gate operational test launch Nation: USA. Agency: USAF. Apogee: 1,000 km (600 mi). References: 1786.

• GT-32PA - 8 RVs Functional Dependency gate operational test launch Nation: USA. Agency: USAF. Apogee: 1,000 km (600 mi). ICBM Demonstration Flight - Dummy Warheads. References: 1944.

• GT-33PA - 8 RVs Functional Dependency gate operational test launch Nation: USA. Agency: USAF. Apogee: 1,000 km (600 mi). ICBM Demonstration Flight. Delayed from March. References: 1944.