San Antonio-class amphibious transport dock

The San Antonio class is a class of amphibious transport docks, also called landing platform docks or LPDs, built for the United States Navy by Ingalls Shipbuilding, part of Huntington Ingalls Industries. The ships replace the Austin, Newport, Anchorage and Charleston classes and are used to embark and land Marines, their equipment and supplies by air cushion or conventional landing craft and amphibious assault vehicles, supported by helicopters or MV-22 Osprey tilt-rotor aircraft. Each ship is 684 feet long and 105 feet wide, displaces about 25,300 tons at full load and has four sequentially turbocharged Colt-Pielstick diesel engines, built in the United States by Fairbanks Morse, driving two shafts at 41,600 shaft horsepower for a speed above 22 knots. The lead ship, USS San Antonio, was delivered in 2005, and the Navy decided in 2018 to build a second flight of 13 ships, the first being Harrisburg.