Austal to modify bow section engineering on two Navy EPF vessels

March 4 (UPI) -- Shipbuilder Austal USA received a $13.6 million contract with the U.S. Navy to provide an engineering change to two EPF ships, the Defense Department has announced.

The company, headquartered in Mobile, Ala., will incorporate changes to the structural bow section of two of the Navy's under construction Expeditionary Fast Transport ships, identified as EPF 11, USNS Puerto Rico, and EPF 12, USNS Newport.

The EPF is a catamaran based on a commercial design with an aluminum hull. It is built for intra-theater personnel and cargo transport for high-speed sealift operations.

The vessels are designed to operate in shallow-draft ports and waterways for a wide range of activities, including humanitarian assistance and relief operations in small or damaged ports. EPFs can transport 600 short tons 1,200 nautical miles at an average speed of 35 knots. The ships include airline-style seating for 312 embarked forces and fixed berthing for 104.

EPF 11 was christened the USNS Puerto Rico in November 2018. The vessel is the first active ship in naval service to be named for the island territory.

The keel of EPF 12, the future USNS Newport, was laid in January 2019. It is the fourth U.S. Navy vessel to carry the name.

The conversion contract calls for work on both vessels to be conducted largely at Austral USA's Mobile and Pascagoula, Miss., facilities.