The U.S. Navy issued a preliminary contract that will let General Dynamics NASSCO build a sixth in a series of ships for expeditionary warfare.

The Expeditionary Sea Base ship is 775 feet long and includes a raised flight deck that can accommodate four helicopters or tiltrotor aircraft. The ship has berthing for 250 troops.

On Oct. 16, the Navy awarded a $136.7 million contract that will pay for procurement of long-lead-time material, such as diesel engines, propeller and shafting; as well as steering gear components and integrated bridge electronics. Some 3 percent of the work will be performed in Busan, South Korea.

The contract was awarded without competitive bidding, as the government determined there was only one responsible source that could satisfy requirements. The Naval Sea Systems Command of Washington D.C. awarded the contract.

General Dynamics (NYSE: GD) NASSCO builds its ships in Barrio Logan.