USNS Mercy is the lead ship of her class of hospital ships in non-commissioned service with the United States Navy. Mercy was built as a San Clemente-class oil tanker, SS Worth, by National Steel and Shipbuilding Company, San Diego, California, in 1976. Starting in July 1984, she was renamed and converted to a hospital ship by the same company. Launched on 20 July 1985, Mercy was placed in service on 8 November 1986. She has a raised forecastle, a transom stern, a bulbous bow, an extended deckhouse with a forward bridge, and a helicopter-landing deck with a flight-control facility.
Her primary mission is to provide rapid, flexible, and mobile acute medical and surgical services to support Marine Corps Air/Ground Task Forces deployed ashore, Army and Air Force units deployed ashore, and naval amphibious task forces and battle forces afloat. Secondarily, she provides mobile surgical hospital service for use by appropriate US Government agencies in disaster and humanitarian relief, and limited humanitarian care incident to these missions and to peacetime military operations.
Mercy, homeported in San Diego, is normally in reduced operating status. Her crew remains a part of the staff of Naval Medical Center San Diego until ordered to sea, at which time they have five days to fully activate the ship to a NATO Role III Medical Treatment Facility, the highest only to shore-based fixed facilities outside the theater of operations. Like most “USNS” Ships, mariners from the US Navy’s Military Sealift Command are responsible for navigation, propulsion, and most deck duties on board.