The Peacekeeper Rail Garrison is a mobile missile system that was developed by the United States Air Force during the 1980s as part of a plan to place fifty MGM-118A Peacekeeper intercontinental ballistic missiles on the rail network of the United States.
The railcars were intended, in case of increased threat of nuclear war, to be deployed onto the nation’s rail network to avoid being destroyed by a first strike counterforce attack by the Soviet Union. However the plan was cancelled as part of defense cutbacks following the end of the Cold War, and the Peacekeeper missiles were installed in silo launchers as LGM-118s instead.
Two hi-cube boxcars were constructed by St Louis Refrigerator Car Company. They were modified at Westinghouse, receiving bogie trucks, distributing their 550,000 pounds (250,000 kg) of weight over 8 axles. Low-slung beams were added to the underside to level the car against the track during launch. 80-foot (24.38 m) roof panels were designed to fall off when the missile was erected. The Air Force sought US$2.16 billion in fiscal year 1991 to purchase the first seven MX trains.
The deployment plan called for the trains to be permanently based in shelters that would be constructed on Strategic Air Command bases throughout the United States, with the missile crews on continuous alert.However, the plan was canceled as part of defense cutbacks following the end of the Cold War, and the Peacekeeper missiles were installed in silo launchers as LGM-118s instead./source