The Navy's newest warship is slowly disappearing, one molecule at a time.

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 aluminum. And that's one root of the ship's ailment.

Corrosion is a $23-billion-a-year problem in the equipment-heavy U.S. military. But Independence's decay isn't a case of mere oxidation, which can usually be prevented by careful maintenance and cleaning. No, the 418-foot-long warship is 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 – shipboard versions of airplane engines – where steel "impeller housings" come in contact with the surrounding aluminum 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 aluminum ferries for civilian customers. The Navy, for its part, has operated mixed aluminum-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 $400 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 LCSs 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 LCSs 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?

*Photo: Navy

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