Peterson AFB Community
The 21st SW’s ground-based missile warning sites employ solid state phased-array radar systems. Its mission is to detect sea-launched ballistic missile and intercontinental ballistic missile attacks against the continental United States and Canada, and determine the potential number and probable destination of these missiles. The wing has space warning squadrons at Cape Cod AFS, Massachusetts; Beale AFB, California; Cavalier AFS, North Dakota; Thule AB, Greenland; and Clear AFS, Alaska. The wing has a liaison at the missile warning site at Royal Air Force Fylingdales, United Kingdom. All these sites provide continual information as part of an integrated global network of missile warning systems. Missile warning data from these sites are sent to U.S. Strategic Command’s Missile Warning Center at Cheyenne Mountain Air Force Station, Colorado. Data is also sent to the National Military Command Center and USSTRATCOM’s Global Operations Center.
Three of the missile warning sites employ a specific type of phased-array radar called the PAVE Phased Array Warning System. The radar works by sending out a beam formed from several transmitters eliminating the need to move or rotate the radar. The PAVE PAWS radar can electronically change its point of focus in milliseconds, while conventional dish-shaped radar may take up to a minute to mechanically swing from one area to another. Raytheon built the PAVE PAWSradars, with the original AN/FPS-115 becoming operational in the 1970s. The first AN/FPS-123, a more powerful phased-array radar, was operational on April 4, 1980, at Cape Cod Missile Early Warning Station, now called Cape Cod AFS in Massachusetts. The AN/FPS-123 was subsequently installed at Beale AFB, California; Eldorado AFB, Texas; and Robins AFB, Georgia. These roughly 90-foot diameter circular-panel radars are mounted on two or more walls of a triangular-shaped pyramid structure. PAVE PAWS can detect and track targets a range of about 3,000 nautical miles. There were originally four continental U.S. sites. Two of the original CONUS sites, Cape Cod AFS, operated by the 6th Space Warning Squadron, and Beale AFB, operated by the 7th Space Warning Squadron, are still operational.
Beale recently completed a weapon system software update called Upgraded Early Warning Radar, which changed the radar’s nomenclature to AN/FPS-132. This was the first radar site to complete the upgrade in the 21st SW. The radars at RAF Fylingdales and Thule AB were subsequently upgraded to the AN/FPS-132 UEWR system. The Upgraded Early Warning Radar (UEWR) software’s enhanced capability added the corollary mission of missile defense in support of the Ground-based Midcourse Defense (GMD) element of the Ballistic Missile Defense System (BMDS). This program’s objective is the defense of the United States against a threat of a limited long-range ballistic missile attack through the use of interceptor missiles at Vandenberg AFB, California, and Fort Greely, Alaska. The other two CONUS PAVE PAWS sites at Robins AFB, Georgia, and Eldorado AFS, Texas, have now ceased operations. The AN/FPS-123 radar from Eldorado AFS was relocated to Clear AFS and is operated by the 13th Space Warning Squadron and 213th Space Warning Squadron (Alaskan Air National Guard), replacing the older Ballistic Missile Early Warning System mechanical radar there. Similar radars replaced the BMEWS mechanical radars at the 12th Space Warning Squadron at Thule AB, and at RAF Fylingdales. Fylingdales is unique, having three radar faces covering 360 degrees in azimuth, while the Clear AFS and Thule AB models each have two radar faces covering 240 degrees in azimuth. Even though none of the BMEWS mechanical radars are still in operation, for programmatic reasons Thule AB is still referred to as BMEWS Site I, Clear AFS is referred to as BMEWS Site II and Fylingdales is referred to as BMEWS Site III.
The 10th Space Warning Squadron at Cavalier AFS, North Dakota, operates the AN/FPQ-16 phased-array radar called the Perimeter Acquisition Radar Attack Characterization System. The PARCS radar has a single field of view extending north over the Hudson Bay, covering 120 degrees in azimuth. It provides tactical warning, attack characterization and assessment of ballistic missile attacks. It is the only missile warning sensor that can determine the type of missiles used in a raid and predict impact times and locations in the continental United States.