SASEBO NAVAL BASE, Japan -- For the second time in three months, the first-in-class littoral combat ship USS Freedom has found itself pier-side because of maintenance issues.

Repairs are under way after the crew of the $500 million ship found seawater contamination in the starboard steerable water-jet hydraulic system Oct. 24 while preparing to head to sea, Navy officials said this week. The ship’s commanding officer, Cmdr. Patrick Thien, decided the ship could navigate safely with both water-jets functioning properly in the port drive train but that it was better to address the issue ahead of international exercises in a couple of weeks.

Navy officials have said the Freedom’s maintenance problems have been routine and consistent with new systems on first-in-class ships. The Freedom has two independent drive trains consisting of steerable and reversible water-jets as well as a boost jet for higher speeds; most Navy vessels have traditionally used rudders and propellers for steering and propulsion.

“I cannot discuss specific maintenance timelines, but technicians are working quickly to accomplish repairs -- which involve draining the seawater out and restoring the system with new hydraulic oil,” Task Force-73 spokesman Lt. Cmdr. Clay Doss said Tuesday in an email to Stars and Stripes. “I do not expect this problem to affect Freedom’s operational schedule, and the crew continues to make preparations for [Cooperation Afloat Readiness and Training] Brunei in mid-November.”

In July, the Freedom was forced back to port after exhaust leaks in turbochargers for the diesel generators caused one generator to overheat and shut down, ultimately resulting in a loss of propulsion. The crew was able to restore propulsion, and there were no injuries and no damage to the ship.

The Freedom arrived in Singapore in April. It has participated in the International Maritime Defence Exhibition, two separate phases of the naval exercise Cooperation Afloat Readiness and Training with Malaysia and Singapore and hosted “thousands of visitors,” Navy officials said. The Freedom swapped crews in August and is slated to rotate back to San Diego toward the end of 2013.

The hydraulic system leak is the latest hiccup for the heavily scrutinized LCS program. Since its inception in 2002, concerns over cost overruns and structural deficiencies that included hull cracks, corrosion and system failures have given way to doubts about its combat effectiveness, design and durability.

In March, while the Freedom traversed the Pacific en route to its inaugural overseas deployment, media reports cited commander of naval surface forces, Vice Adm. Tom Copeman, as criticizing the littoral ships for lacking firepower. Two weeks later, a fire was reported aboard the LCS Coronado during sea trials.

In July, the Government Accountability Office recommended the Navy slow construction of the ships so more testing can be done to determine whether they can meet the Navy’s needs. The Navy disputed the recommendation and pledged to move ahead with the current delivery schedule.

A month later, chief of naval operations Adm. Jonathan Greenert established a working group -- the LCS Council -- to evaluate the LCS program as well as crew rotations and maintenance plans.

Despite its detractors, littoral combat ships have long been the apple of the Navy’s eye and are being slowly phased in to replace aging Oliver Hazard Perry-class frigates, Avenger-class mine countermeasure ships and Osprey-class coastal mine hunters.

The ships were designed to be fast with a shallow draft so they can operate near shore where other Navy ships have been unable to go. They can be fitted with interchangeable mission packages like surface warfare, minesweeping and anti-submarine warfare.

The Freedom is fitted with a surface-warfare mission package and maritime-security module. It has a complement of 91 sailors on board, including mission package personnel and an aviation detachment to operate an embarked MH-60 helicopter.

By the end of 2021, the Navy expects to have 24 littoral ships under contract, with 16 assigned to the Pacific Fleet.