
This isn’t a sequel to the 1984 sci-fi flick The Philadelphia Experiment, in which a Navy destroyer-escort vanishes through a time portal in Pennsylvania only to reappear in Nevada, 40 years later.
No, this time the disintegration is real. And so is the resulting tension between the Navy and the disappearing warship’s upstart builder.
The afflicted vessel is USS Independence, the second in the sailing branch’s fleet of fast, reconfigurable Littoral Combat Ships. Eventually, these ships are supposed to be the “workhorses” of tomorrow’s Navy.
As Bloomberg reported, the Navy has discovered “aggressive” corrosion around Independence‘s engines. The problem is so bad that the barely year-old ship will have to be laid up in a San Diego drydock so workers can replace whole chunks of her hull.
In contrast to the first LCS, the steel-hulled USS Freedom, Independence is made mostly of aluminium. And that’s one root of the ship’s ailment.
Corrosion is a $US23-billion-a-year problem in the equipment-heavy US military. But Independence‘s decay isn’t a case of mere oxidation, which can usually be prevented by careful maintenance and cleaning. No, the 127m long warship is basically dissolving, due to one whopper of a design flaw.
There are technical terms for this kind of disintegration. Austal USA, Independence‘s Alabama-based builder, calls it “galvanic corrosion.” Civilian scientists know it as “electrolysis.”It’s what occurs when “two dissimilar metals, after being in electrical contact with one another, corrode at different rates,” Austal explained in a statement.
“That suggests to me the metal is completely gone, not rusted,” naval analyst Raymond Pritchett wrote of Independence‘s problem.
Independence‘s corrosion is concentrated in her water jets – basically, shipboard versions of aeroplane engines – where steel “impeller housings” come in contact with the surrounding aluminium structure. Electrical charges possibly originating in the ship’s combat systems apparently sparked the electrolysis.
It’s not clear why Austal and the Navy didn’t see this coming. Austal has built hundreds of aluminium ferries for civilian customers. The Navy, for its part, has operated mixed aluminium-and-steel warships in the past.
But Independence – the Navy’s first triple-hull combatant – could be a special case for both the builder and the operator. For all Austal’s chops building civilian ferries, the Australian company is new to the warship business. Austal set up shop near Mobile in 1999. Today, the shipyard has contracts to build 10 LCS plus several catamaran transports for the Navy.
From the Navy’s point of view, Independence and the other Littoral Combat Ships are unique. As in, uniquely cheap. Each vessel is supposed to cost just $US400 million, compared to more than a billion bucks for a larger, all-steel Arleigh Burke-class destroyer.
Lots of things – major weapons, for one – have been left off the LCS in order to keep the price down. The list of deleted items includes something called a “Cathodic Protection System,” which is designed to prevent electrolysis.
Independence will get the protection system installed at the first opportunity, and future LCS will include it from the beginning, according to Pritchett.
But instead of simply filing the corrosion issue under “lessons learned,” Austal seems determined to blame its customer. “Galvanic corrosion has not been a factor on any Austal-built and fully-maintained vessel,” Austal stressed, implying that Independence hasn’t been “fully maintained” by a negligent Navy.
That’s an, ahem, interesting approach to customer relations for America’s newest warship-builder.
And things could get worse, as more LCS enter the fleet. “I suspect there will be other public problems revealed over time that will require relatively simple, albeit costly, solutions,” Pritchett wrote. Will Austal also blame the Navy the next time a glitch appears in the ships it builds?




















Shane
Friday, June 24, 2011 at 8:33 AMDavid, what have you done to determine where the problem lies? Let me see, it was an Australian company so it must be them becuase we are American duh. Good work. If the US navy didn’t install a cathodic protection system the ship will corrode. Who’s responsibility was is to supply the protection system? That’s the question here, not the pathetic uninformed drivel you have spewed out. If the people in the navy are as talented as US journalists I think I know where the problem lies.
bryan
Friday, June 24, 2011 at 12:07 PMThe article is fine. Its balanced and informed. The problem is that Austal is listed and its shareholders are atypical…egoic, ranting children, like Shane, who cant stand the thought of their investment being challenged
klaw
Friday, June 24, 2011 at 11:32 AMGalvanic corrosion is a very common problem when dissimilar metals are used in any sort of structure. The causes and solutions to this sort of issue are very well known in engineering circles.
It seems fairly likely that since the US Navy is not accustomed to aluminium-hulled ships, they won’t be familiar with (or fully understand the importance of) the precautions and procedures for keeping dissimilar metals isolated from each other.
I agree with Shane – this article is drivel. The builder has a good track record with similar designs, and even the best builder can’t prevent problems that arise through the lack of proper maintenance.
dave
Thursday, June 30, 2011 at 1:04 AM+1
Nick
Friday, June 24, 2011 at 12:21 PMThe first thing you get taught in materials engineering is how important it is to avoid dissimilar metal corrosion. Boats are generally built to avoid it in the first place rather than excessive expectation on the owner to keep up maintenance.
So im going to have to disagree with the previous two comments and say that this isnt just the Navy’s fault (though im sure they could have done things better). Its also a bit rich to call this article drivel imo. It seems well researched to me!
Also im an australian so dont go calling me biased….
Nathan
Friday, June 24, 2011 at 1:03 PMYep, always someone else’s fault. Sue.
Ollie
Friday, June 24, 2011 at 1:13 PMIt’s not just dissimilar metals either, just your bog standard seawater and metal doesn’t help things to begin with. They probably didn’t want to spend the money on anodes trololol
Ollie
Friday, June 24, 2011 at 1:15 PMThe article is rubbish btw, written by someone who knows nothing about the subject, just a cut-and-paste job. Have you guys ever considered consulting an expert?