Austal says it has delivered its third Joint High Speed Vessel to the US Navy.
The USNS Millinocket is the third such vessel under a 10-ship, $US1.6 billion contract.
Chief executive Andrew Bellamy said the Joint High Speed Vessel program had matured through the implementation of productivity and efficiency improvements at Austal's US shipyard since construction commenced on the first vessel.
"We have taken a very proactive approach in making operational improvements at the shipyard through each step of the JHSV program," he said.
"It is pleasing to see the benefits of these improvements, with Austal's JHSV program maturing into the phase of efficient, serial production of the vessels."
Austal delivered the first Joint High-Speed Vessel, USNS Spearhead, in December 2012 and the second, USNS Choctaw County, in June 2013.
Ships under construction are JHSV 4, which was christened in January and is being prepared for sea trials, JHSV 5, which has begun final assembly, and JHSV 6, which commenced construction in January in the module manufacturing facility.
Five Independence-variant Littoral Combat Ships are also under construction at Austal's US shipyard under the company's separate 10-ship, $3.5 billion contract with the US Navy.
Austal shares were up one cent, or 1.04 per cent, to 97 cents at the open of trade.