Navy Finds 'Aggressive' Corrosion on Austal's Combat Ship (Littoral Combat Ship)

San Francisco Chronicle ^ | June 17, 2011 | Steven Komarow, Ann Hughey.

[tlb]

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,".

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.

Austal won a $465 million contract that could reach as much as $3.78 billion if all options are exercised. Building all 55 ships will cost the Navy at least $37.4 billion.

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.

[tlb]

When I first heard of this program, I thought we would be developing a fast light Corvette class like the Swedes sail. Maybe it's not too late to buy some of their boats.

[SWAMPSNIPER]

Electrolysis is going to be a big problem with any aluminium hull in saltwater.

[DesScorp]

just cancel them, already

[DesScorp]

just cancel them, already

[Roccus]

I worked on aluminum head fishing boats built in the early 70’s that are still working fine. Granted, they were hauled yearly and zincs were used liberally, so I’m not sure that would meet Navy requirements.

[Tainan]

No problem...

[SWAMPSNIPER]

One of my customers painted the loser unit of his outboard with copper anti fouling paint, 6 weeks later he fired it up but the boat wouldn’t move. There was nothing left below the waterline.

[Roccus]

LOL!!!

Though it sounds like a bit of an exaggeration, that IS funny!

[mazda77]

Maybe they need to consider carbon fiber for the prop shafts. Racers I know have gone to carbon fiber driveshafts in an effort to save weight so there might be an alternative win for this possible solution. Size is not an issue as Boeing is maing the 787 totally of composites. Then they would eliminate the dissimilar metals concerns.

[ProtectOurFreedom]

I guess it really was a “loser” unit, huh?

[Roccus]

According to this it has carbon fiber shaftlines. However, propulsion comes from jet drives, not standard propellers (except for the bow thrusters)

http://en.wikipedia.org/wiki/USS_Independence_(LCS-2)

(For some reason the last “)” is not picked up by the hyperlink, so you'll have to click a second time once you reach wiki.)

[Loud Mime]

[MontaniSemperLiberi]

“Building all 55 ships will cost the Navy at least $37.4 billion.”

Which would we rather have? 55 LCS’s or 6 aircraft carriers?

[john drake]

I guess I’m dumber than a box of rocks; wouldn’t the engineers have known that partnering these metals in saltwater would’ve caused the accelerated corrosion or don’t they test, or read of prior results, before going ahead and spending billions of tax dollars? I guess I’m even more suspicious thinking that they know these products will need more regular maintenance thereby keeping their coffers full of annual repair bill invoices. Greed, stupidity, and outright fraud, someone should go to jail, but they won’t. Worst case, you’re in the middle of an effin’ global war and your ships spend too much time in drydock being repaired because of something like this. Am I dreaming or what? Who were the engineers on this project, chicoms, russkies or muslims? Just askin’.....

[grey_whiskers]

One of my customers painted the loser unit of his outboard with copper anti fouling paint, 6 weeks later he fired it up but the boat wouldn’t move. There was nothing left below the waterline.

"Loser unit" sounds like the right name.

Cheers!

[grey_whiskers]

Who were the engineers on this project, chicoms, russkies or muslims? Just askin’.....

My vote would be Chicom saboteurs or haughty H1Bs from India.

Cheers!

[tanknetter]

I guess I’m dumber than a box of rocks; wouldn’t the engineers have known that partnering these metals in saltwater would’ve caused the accelerated corrosion or don’t they test, or read of prior results, before going ahead and spending billions of tax dollars?

You'd think. But there are other possibilities as well. For example, the engineers may have known about the potential for corrosion and come up with mitigation strategies that simply didn't work when translated from a lab/test environment to the real world.

Also, the first two LCS ships (Freedom, which is a monohull design and Independence, which is the trimaran) were bought under the "try before buy" principle and have been run VERY hard. Possibly much harder, and in a shorter period, than the follow on ships will be. AND examined earlier and in a more thorough manner - meaning that the problem might have gone unnoticed in "production" ships (like what happened with the structural issues cropping up in the Burkes.)

Beyond that, it's possibly a construction or operational rather than engineering issue. Not putting the right amount of anti-corrosion material on during construction, or not maintaining it during service use.

[driftdiver]

how many aircraft carriers do we need?

the cost of a carrier is much more than just the ship, there are all the other ships and aircraft which comprise a carrier group.

[BuffaloJack]

I’m going to blame the tree-huggers for this one.
They used to use zinc chromate primers on aluminum and they they put an epoxy paont over that. The zinc chromates were banned by the EPA, so now everything corrodes quickly. Everything is fine until the paint layer gets its first pinhole, then the aluminum is zoomed. The reason older aluminum hulls were OK is the primers that were used and no longer allowed.

[Scotsman will be Free]

First the Navy’s gotta spend umpteen billion trying to fix the problem, spend more billions buying defective equipment and at the end of the day let the program die quietly.