Find a Security Clearance Job!


Early Warning Radars

  • AN/FPS-17
  • AN/FPS-50 Ballistic Missile Early Warning System [BMEWS]
  • AN/FPS-85 Spacetrak Radar
  • AN/FPS-92 Ballistic Missile Early Warning System [BMEWS]
  • AN/FPS-115 PAVE PAWS Radar System
  • AN/FPS-120 Solid State Phased-Array System [SSPARS]
  • AN/FSQ-76 / AN/FRT-80 / 440L OTH Forward-Scatter
  • AN/FSS-7 ["Fuzzy Seven"]

  • The properties of range, speed, payload, accuracy, and readiness of offensive missiles were of great consequence to the fundamental strategies being pursued by each side. As ICBMs were perfected, vast improvements resulted from various technologies. As one example, the technology of fuels progressed very rapidly and, by making it possible to maintain missiles in readiness for extended periods, also permitted their emplacement in underground silos, hardened against explosion. The vulnerability of the nuclear deterrent was ensured thereby, it seemed. The parallel development of missiles for firing from submarines greatly increased the U.S. capability to survive a first strike. The first generation missiles, however, were soft because they had to be fueled regularly to be made ready, and were deployed above ground. They represented a vulnerable deterrent.

    The principal impact of the initial ICBM had appeared to be the capability to make surprise attack much easier. Soft targets were tempting. Quickly the need for some warning against the Soviet ICBM threat gave rise to the U.S. radar warning systems BMEWS, Ballistic Missile Early Warning System. Since BMEWS could “see” a missile about 15–20 minutes before that missile would arrive in the United States, SAC bombers could be on ground alert or airborne and the U.S. retaliatory force, which was then vulnerable to attack, would be protected against destruction through adequate warning. (BMEWS was oriented to the north and would not provide warning against the submarine-launched missile attack.)

    Radar warning of an attempted Soviet missile attack would permit SAC aircraft to become airborne although warning would pose the difficult question of whether ICBMs of the U.S. retaliatory force should be launched on the basis of radar warning alone. The aircraft could be recalled if necessary; the missiles could not.

    Since BMEWS could provide only about 15 minutes of warning time, development funds were requested for MIDAS which might be able to provide about 30 minutes of warning. Missile warning through BMEWS and OTH forward-scatter radars would remain basically the same pending completion of the OTH-B study.

    The Air Force was initially assigned responsibility for developing the ballistic missile early warning system on 5 October 1956 when the then Special Assistant for Guided Missiles to the Secretary of Defense informed the Secretaries of the Army and Air Force of their Services’ responsibility in the antiballistic missile field. This was subsequently confirmed by Secretary of Defense Charles E. Wilson on 25 April 1957 when he directed the Air Force to develop the anti-ICBM early warning system, to carry out research and development on the advanced acquisition radars required by the active anti-ICBM system, and to study the communications between these radars and the active portion of the system. Soviet announcement of a successful ICBM launching in August of 1957 followed shortly thereafter by Sputnik I, added impetus to the program.

    The missile and space surveillance and warning system consisted of five systems and a space computational center located in the NORAD Cheyenne Mountain complex. The five systems are: the Ballistic Missile Early Warning System; the Defense Support Program (DSP) formerly called Project 647; the Forward Scatter over the Horizon Radar (440L) system; the Sea-Launched Ballistic Missile Warning System; and the Space Detection and Warning System.

    The earliest space-based missile warning system was the Missile Defense Alarm System (MIDAS) satellite, which was part of the Air Force missile warning program in the late 1950s.3 It was designed to detect and track hot exhaust gases from intercontinental ballistic missiles (ICBM) during the boost phase. In 1963, MIDAS became the first spacebased system to accurately detect a missile launch when it reported on both Minuteman and Polaris ICBM test launches, which were deliberately scheduled to coincide with the MIDAS orbit.4 MIDAS was eventually phased out in the late 1960s in favor of the Defense Support Program (DSP), which has a more advanced sensor design and a more robust spacecraft platform. DSP has been the stalwart of missile warning since the 1970s.

    Join the mailing list