An ammunition ship is a warship specially configured to carry ammunition, usually for Navy ships and aircraft. Their cargo handling systems, designed with extreme safety in mind, include ammunition hoists with airlocks between decks, and mechanisms for flooding entire compartments with sea water in case of emergencies. They most often deliver their cargo to other ships using underway replenishment, using both connected replenishment and vertical replenishment. To a lesser extent, they transport ammunition from one shore-based weapons station to another.
U.S. Navy ammunition ships are frequently named for volcanos. During World War II, U.S. Navy ammunition ships were converted from merchant ships or specially built on merchant ship hulls, often of type C2. They were armed, and were manned by Navy crews. Several of them were destroyed in spectacular explosions during the war. Notable among them was USS Mount Hood, which exploded in the Admiralty Islands on November 10, 1944.
Contemporary U.S. ammunition ships of the Kilauea class are specially designed for their mission, which also includes carrying dry and refrigerated cargo. They are unarmed and are manned by civilian crews.