Boeing-built Minuteman missile systems, operated by the Air Force Combat Command, are long-range, solid-fuel, three-stage, intercontinental ballistic missiles capable of carrying single or multiple nuclear warheads. The program, which began in 1958, is one of the company's longest military contracts. By April 1967, 1,000 Minuteman missiles were operational and installed in six sites across the country. Minuteman II, first launched in 1964 and shown here, was capable of striking from six to eight targets with far greater accuracy than its predecessor. The next version, Minuteman III, was first launched in 1968, with more accuracy, range and target capability. By 1975, the 1,000 Minuteman U.S. missiles were either Minuteman IIs or IIIs. The company will continue to support the Air Force with system evaluation, testing, training and modernization at least through the year 2010.