Austal has won a $7 million engineering services contract to support testing of a class of warship it builds for the US Navy.
The shipbuilder said the work was part of the navy's survivability testing program for the Independence-variant littoral combat ship.
The work was critical to class qualifications and the ships' eventual deployment, Austal said.
The $6.7 million contract modification is for the fabrication and assembly of a live fire test module.
The work will be done at Austal's US shipyard in Mobile, Alabama.
The shipbuilder has a $3.5 billion contract with the navy to build 10 LCS vessels. Five are under construction.
LCS vessels, which are also built by Lockheed Martin, have been criticised by some US political and defence figures over its ability to withstand combat operations.
The US Defence Department has proposed cutting the total number of LCS vessels it will order from 52 to 32.
Austal's shares were down 3 cents, or 3 per cent, 97 cents at 12.08pm.