View source for LPD - Amphibious Transport Dock Vessel

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.[1] 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 LPDs by incorporating both a flight deck and a well deck that can be ballasted and deballasted to support landing craft or amphibious vehicles.

http://en.wikipedia.org/wiki/Amphibious_transport_dock