LGM-118 Peacekeeper

The LGM-118 Peacekeeper, first known as the MX or

The LGM-118 Peacekeeper, first known as the MX or "Missile-X", was an encapsulated ICBM and the first U.S. ICBM to use a Cold Launch System. Although larger than the LGM-30 Minuteman, the MX was designed to fit inside existing hardened LGM-30 Minuteman ICBM silos as a silo-based ICBM and later as a mobile ICBM via the Peacekeeper Rail Garrison. The first 50 MX ICBMs were scheduled to be deployed and full initial operational capability achieved by the United States beginning and ending in 1986. The MX Peacekeeper was a MIRV missile platform that could carry up to 12 re-entry vehicles, each armed with a 300-kiloton W87 warhead in a Mk.21 reentry vehicle (RV). The first 50 missiles were deployed starting in 1986, after a long and contentious development program that traced its roots into the 1960s with the first generation ICBMs. Initial LGM-118A missile testing began 1971, with full-scale development starting in 1974. The first flight test occurred in 1983. This test also included the successful test deployment of six inert (unarmed) Re-entry vehicles, each hitting pre-planned targets. Initially, 100 MX ICBMs were planned to be built and deployed, but Congressional and budgetary concerns eliminated the final procurement.
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