The littoral combat ship Independence hit 43 knots while underway for builder's trials in July, running both its diesels and turbines, but not to their limits. (Dennis Griggs / General Dynamics)
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The littoral combat ship Independence hit a speed of 43 knots on its builder's trials in late July while running at less than full power, but problems with its propulsion plant will necessitate at least a second set of tests.
The Navy's second LCS — an aluminum trimaran built by a contractor team helmed by General Dynamics — took trips to sea and back from its shipyard in Mobile, Ala., as engineers tested its engines and systems.
Like the first LCS, the Lockheed Martin-built Freedom, Independence has a combined diesel-and gas-propulsion plant. Independence was running both its diesels and turbines, but not to their limits, when the ship reached its high trials speed.
But engineering problems delayed for three days the start of its trials, and other problems underway have kept it from making a true full-power run.
"During the buildup to full-power testing, we experienced a leak in the port gas turbine shaft seal, which we're now troubleshooting in order to determine the best course for corrective action," Jeff Geiger, president of GD's Bath Iron Works shipyard, said in a statement.
"We've determined that the best path forward is to re-sequence the remaining trial events while we continue other work necessary to ready the ship for Navy acceptance trials later this summer. An additional underway period will be conducted before acceptance trials. ... We do not expect that this adjustment will affect the planned delivery of the ship later this year."
In addition to wondering about what speeds it would reach, observers also have been curious about how Independence, with its stabilizing outrigger hulls, would handle at sea. General Dynamics declined to arrange interviews with technicians who had been aboard the ship underway, but spokesman Jim DiMartini released a comment from one of the ship-riders:
"This ship rides like nothing I've ever gone to sea on. Inside the ship, it was hard to get a good sense of just how fast we were actually going. The usual kind of motion and vibration you feel from a conventional ship at higher speeds just wasn't there. There's no bow wave. It slices through the water and what really blew me away was how well the ship turns at high speed, almost like a 90-degree pivot and with virtually no heel."
The wave-splitting style of Independence is different from Freedom, which planes above the waves like a Jet Ski to reach its high speeds.
More tests for LCS 1
As Independence made its first trips to sea and back, engineers at Naval Station Norfolk, Va., continued their tests on Freedom. The ship had its first fitting of one of the 30mm modular guns that the hulls will carry in their surface-warfare configurations, said Guy Schein, a spokesman for the Navy's program executive officer for littoral and mine warfare. The gun was lowered into the space set aside for it on the ship's superstructure and plugged into the ship's combat system, but not fired.
Both LCS designs have two spaces that can accept the 30mm guns or a box of Non-Line-of-Sight missiles, a weapon in development with the Army.
In July, Freedom also test-fired its 57mm gun, Schein said, ticking off more accomplishments on what will be a long checklist before the ship can enter the fleet.
The littoral combat ship Freedom's original schedule didn't call for a deployment until 2011, after the ship had tested its mission modules at the Naval Surface Warfare Center in Panama City, Fla., and then moved to its permanent home port at Naval Base San Diego. But in June, Chief of Naval Operations Adm. Gary Roughead ordered a study of the possibility that Freedom could sail earlier than that, although Navy officials won't say where they're considering sending it.
Navy spokesman Lt. Clay Doss said July 30 that study continues, and that the Navy hadn't yet decided whether whether or where to deploy Freedom.
As for Independence, it's scheduled to be commissioned this fall.