Amphibious transport dock

An amphibious transport dock (LPD) is a warship that embarks, transports, and lands elements of a landing force for expeditionary warfare missions. The United States Navy operates several of this type of ship; their helicopters, vertical take-off and landing aircraft, and air-cushion or conventional landing craft[?] support of the United States Marine Corps's "vertical envelopment" assault doctrine.

Amphibious transport docks perform the mission of amphibious transports[?], amphibious cargo ships[?], and the older LPDs by incorporating both a flight deck and a well deck that can be ballasted and deballasted to support landing craft or amphibious vehicles.