Sea-Based X-Band Radar is a floating, self-propelled, mobile radar station designed to operate in high winds and heavy seas. It is part of the United States Government's Ballistic Missile Defense System.
The Sea-Based X-Band Radar is mounted on a 5th generation Norwegian-designed, Russian-built semi-submersible twin-hulled oil-drilling platform. Conversion of the platform was carried out at the AMFELS yard in Brownsville, Texas; the radar mount was built and mounted on the platform at the Kiewit yard in Ingleside, Texas, near Corpus Christi. It will be based at Adak Island in Alaska but can roam over the Pacific Ocean to detect incoming ballistic missiles.
Specifications
Platform length: 116 meters (380 feet)
Platform height: 85 meters (280 feet) from keel to top of radar dome
Cost: $900 million
Crew: Approximately 75 members
Radar range: Classified
The platform is part of the Ground-Based Midcourse Defense (GMD) system being deployed by MDA. Being sea-based allows the platform(s) to be moved to areas where they are needed for enhanced missile defense. Fixed radars provide coverage for a very limited area due to the curvature of the Earth.
The first such vessel is based in Adak Island, Alaska, part of the Aleutian Islands. From that location it is able to track missiles over both North Korea and China. Although her homeport is in Alaska, she will be tasked with moving throughout the Pacific ocean to support her mission.
Her radar is described by Lt. Gen Trey Obering (director of MDA) as being able to track an object the size of a baseball over San Francisco from the Chesapeake Bay (approximately 2900 miles). The radar will guide land-based missiles from Alaska and California, as well as in-theatre assets.
As of 2006, the system has undergone six successful intercept tests (since 2002).