Amphibious transport dock

An amphibious transport dock, also called a landing platform/dock (LPD), is an amphibious warfare ship, a warship that embarks, transports, and lands elements of a landing force for expeditionary warfare missions. Several navies currently operate this kind of ship. The ships are generally designed to transport troops into a war zone by sea, primarily using landing craft, although invariably they also have the capability to operate transport helicopters.

Amphibious transport docks perform the mission of amphibious transports, amphibious cargo ships, and the older LSDs by incorporating both a flight deck and a well deck that can be ballasted and deballasted to support landing craft or amphibious vehicles. One of the main differences between LSDs and LPDs is that while the former have a helicopter landing deck, the latter have hangar facilities in addition to a landing deck.

The well deck of the HNLMS Rotterdam

Aviation hangar of the Rotterdam-class HNLMS Johan de Witt

Stern of the USS Juneau ballasted for amphibious operations

The open well deck of the French ship Siroco

The well deck of the USS San Antonio

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