First acquired in 1985, the Sea Shadow was never intended to be mission capable.
Instead, the ship was built to test stealth and automation technology. The sharp angles on the ship reflect designs that had previously proven successful for Lockheed's stealth Nighthawk attack aircraft.
The Sea Shadow's raised hull builds upon older technology that is widely used in ferry design for enhancing stability. The Sea Shadow was designed to be able to withstand 18-foot high waves.
The Sea Shadow was small and cramped. It was only 160 feet long, could only fit 12 bunks, and only had a small microwave, refrigerator, and table for the crew.
Although the Sea Shadow was taken out of service in 2006, it still influenced later classes of ships. Its low radar cross section, for instance, informed the design of subsequent US Navy destroyers.