The U.S. Navy has discovered “aggressive” corrosion in Austal Ltd.’s first new combat ship designed for operating close to shore.
The corrosion is in the propulsion areas of the USS Independence, the Littoral Combat Ship built by the Mobile, Alabama-based subsidiary of Australia’s Austal and General Dynamics Corp.
“This could be a very serious setback,” said Norman Polmar, an independent naval analyst and author in Alexandria, Virginia. “If the ship develops a serious flaw, you’re not going to continue producing them.”
Permanent repair will require drydocking the ship and removing its “water jets,” a key component of the propulsion system, the Navy said in a written statement to congressional appropriations committees provided to Bloomberg News.
Aluminum-hulled ships such as Austal’s tend to rust faster than steel-hulled ships, Polmar said. “But I’m surprised it happened so early,” he said. “This ship is brand new.”
The corrosion discovery in a ship that was commissioned in January 2010 marks another blow to the Littoral Combat Ship program, planned to ultimately consist of 55 ships. In February, the Navy discovered another ship in the series, from another construction team, had a crack through the hull.
Close to Shore
The Littoral Combat ships are designed to operate closer to shore than the rest of the Navy's surface fleet. They would make up about 17 percent of the Navy’s planned 313-ship fleet. Missions include clearing mines, hunting submarines and providing humanitarian relief.
The Navy in December awarded contracts for as many as 10 Littoral Combat ships to each of two teams of builders, led by Lockheed Martin Corp. and Austal.
Austal won a $465 million contract that could reach as much as $3.78 billion if all options are exercised, the Navy announcement said. Building all 55 ships will cost the Navy at least $37.4 billion, according to a Pentagon report released in April.
Officials were concerned about the potential for corrosion during construction of the ship because of “dissimilar metals,” particularly near the steel propulsion shafts, the Navy memo said.
Temporary repairs will allow the ship to operate safely in the interim, the Navy said. The Littoral Combat Ships are designed to last about 25 years. Each ship is expected to cost about $36.6 million a year to operate and support.
The Navy is buying two versions from two teams of builders. The other team consists of Bethesda, Maryland-based Lockheed and Marinette Marine Corp. of Marinette, Wisconsin.
The first Lockheed ship developed a crack as long as six inches through its hull during sea trials in February, prompting a Navy investigation of the design.
Calls to Austal and calls and e-mails to General Dynamics weren’t immediately returned.
The Austal ship is now in Mayport, Florida, undergoing additional testing, the Navy said in its statement. A permanent repair of the existing corrosion damage would be conducted next year, the Navy said.
The Navy statement did not provide an estimate of the cost of the repair work.