Depot ship
A depot ship is an auxiliary ship used as a mobile or fixed base for submarines, destroyers, minesweepers, fast attack craft, landing craft, or other small ships with similarly limited space for maintenance equipment and crew dining, berthing and relaxation. Depot ships may be identified as tenders in American English. Depot ships may be specifically designed for their purpose or be converted from another purpose.
Function
Depot ships provide services unavailable from local naval base shore facilities. Industrialized countries may build naval bases with extensive workshops, warehouses, barracks, and medical and recreation facilities. Depot ships operating within such bases may provide little more than command staff offices, while depot ships operating at remote bases may perform unusually diverse support functions. Some United States Navy submarine depot ships operating in the Pacific during World War II included sailors with Construction Battalion ratings to clear recreational sites and assemble buildings ashore, while the Royal Navy mobile naval bases included specialized amenities ships to meet recreational needs of British Pacific Fleet personnel.