San Antonio-class amphibious transport dock

The San Antonio class is a class of amphibious transport docks, also called a "landing platform, dock" (LPD), used by the United States Navy. These warships replace the Austin-class LPDs (including Cleveland and Trenton sub-classes), as well as the Newport-class tank landing ships, the Anchorage-class dock landing ships, and the Charleston-class amphibious cargo ships that have already been retired.

Twelve ships of the San Antonio class were originally proposed, their original target price was US$890 million; as built, their average cost is $1.6 billion. Defense Authorization for Fiscal Year 2015 included partial funding for the twelfth San Antonio-class ship. As of December 2022 eleven warships of this class were in service with the U.S. Navy, with an additional three ships under construction. The Navy decided in 2018 to produce a second flight of 13 planned LPD Flight II ships, for a total of 26 in the LPD 17 class; LPD 30, Harrisburg, is the first Flight II ship.

Design

The San Antonio class was designed to provide the Navy and U.S. Marine Corps with modern, sea-based platforms that are networked, survivable, and built to operate with 21st century transformational platforms, such as the MV-22 Osprey, the (since canceled) Expeditionary Fighting Vehicle (EFV), Landing Craft Air Cushion (LCACs), and future means by which Marines are delivered ashore. The ship is more than 45 percent larger than the Austin class, displacing more than 25,000 tons at full load. It carries fewer troops, but has twice as much space for vehicles, landing craft, and aircraft. The ships are also suited to act as recovery ships for spacecraft, with a floodable well deck at the back of the vessel into which a capsule can float; Portland was the recovery ship for the Orion capsule of the Artemis 1 uncrewed Moon-orbiting mission on 11 December 2022.