The Sea-Based X-Band Radar is mounted on a fifth generation Norwegian-designed, Russian-built CS-50 twin-hulled semi-submersible drilling rig. The hull was originally built at Vyborg Shipyard, hull number 101. Conversion of the vessel was carried out at the AmFELS yard in Brownsville, Texas; the radar mount was built and mounted on the vessel at the Kiewit yard in Ingleside, Texas. It is nominally based at Adak Island in Alaska but can roam over the Pacific Ocean
The SBX failed during a flight test on January 31, 2010, designated FTG-06. The test was a simulation of a North Korean or Iranian missile launch. The test failure arose from two factors, the first being that algorithms in the SBX radar software which are designed to filter out extraneous information from the target scene were left disengaged for the test, and the second was a mechanical failure in a thruster on the kill vehicle.
During flight test FTG-06a on December 15, 2010, the SBX performed as expected, but intercept of the target missile was again not achieved.