Sea Shadow was built in 1984 to examine the application of stealth technology on naval vessels. She was used in secret until a public debut in 1993. In addition, the ship was designed to test the use of automation to enable the reduction of crew size. The ship was created by the Defense Advanced Research Projects Agency (DARPA), the U.S. Navy and Lockheed. Sea Shadow was developed at Lockheed’s Redwood City, California, facility, inside the Hughes Mining Barge (HMB-1), which functioned as a floating drydock during construction and testing.
Sea Shadow had only 12 bunks aboard, one small microwave oven, a refrigerator and table. She was never intended to be mission capable and was never commissioned, although she is listed in the Naval Vessel Register.
Sea Shadow was revealed to the public in 1993, and was housed at the San Diego Naval Station until September 2006, when she was relocated with the Hughes Mining Barge to the Suisun Bay Reserve Fleet in Benicia, California. Until 2006, Sea Shadow and the HMB-1 were maintained and operated by Lockheed Martin for the U. S. Navy. The vessels were available for donation to a maritime museum.
In 2006, the US Navy tried to sell Sea Shadow to the highest bidder; after the initial offering met with a lack of interest, it was listed for dismantling sale on gsaauctions.gov. The U.S. government mandated that the buyer not sail the ship and is required to scrap the ship. The ship was finally sold in 2012. Sea Shadow was totally dismantled in 2012 by Bay Ship.