The dark waters of the Gulf of Mexico were quickly covered in frothy firefighting foam as they flooded into the well deck of this 25,000-ton ship. Although the vessel’s rolls were gentle in the heat of a summer evening, the water — looking for all the world like a giant bubble bath — sloshed dramatically back and forth, splashing almost to the full three-deck height of the space.
Watching intently were members of the Navy’s Board of Inspection and Survey, who were looking to see if the brand-new Anchorage could successfully ballast down and flood the deck in 15 minutes or less, then pump the space dry in 45 minutes.
“Pretty picturesque, isn’t it?” said Jay Stefany, LPD 17 class program manager at the Naval Sea Systems Command. A veteran of all previous LPD 17 trials, Stefany pointed out that tests of the aqueous film-forming foam system that accounted for the suds weren’t usually done just before the ballast test. What was happening was a bit of accidental timing.
After about an hour of watching the foamy waters rise and then recede in the well deck, Capt. Stephen Mitchell, NAVSEA’s supervisor of shipbuilding on the Gulf Coast, got the word on the test: “They flooded in about 13 minutes, pumped out in a bit over 40. She passed.”
The ballast test was just one of thousands of checks conducted over five days by the INSURV crew to see if Anchorage could pass muster and be accepted as the newest ship in the Navy. From running the engines at full speed to checking to see if doors had properly installed latches, INSURV picked all through the 684-foot-long gator, designed to carry nearly 700 Marines with their gear, vehicles and aircraft, all around the world.
Past INSURV inspections of LPD 17-class ships have not all been routine. The first ship, the San Antonio, was judged to be in poor condition at the time of its acceptance sea trials in June 2005. Even though the ship was accepted by the Navy, numerous problems were known about the San Antonio, and more issues arose after its delivery.
Subsequent ships also displayed serious problems, ranging from poor wiring to oil leaks to computer network issues to problems with how the engines were bolted to the ship. The ships of the LPD 17 class — the largest, most sophisticated and most expensive amphibious transport docks ever built — gained a notorious reputation.
But years of effort by the Navy, its shipbuilders and contractors to fix the ships, improve construction standards and right the program seem to be paying off. With the successful trials of the last two ships — the sixth and seventh ships of a planned class of 11 — the program may finally be entering a new level of maturity.
“The LPD 17 class has matured into a model program,” Rear Adm. Rob Wray, president of INSURV, said July 3 in an email after going over the results of Anchorage’s sea trials. “Early problems with the first ship have been identified and rectified; recent ships have had very few major deficiencies during acceptance trials. Huntington Ingalls Industries is doing good work, at both shipyards, and INSURV scores and statistics bear that out.”
Running through the paces
The inspection team came aboard June 18 at the HII shipyard in Avondale, La., just up the Mississippi River from New Orleans.
After two days of pierside inspections, which included “cold checks” of the diesel main propulsion engines and generators and operation of the ship’s large knuckleboom crane, Anchorage cast off in the pre-dawn hours of June 20, heading past New Orleans and continuing more than 100 miles down the river to the Gulf.
The INSURV team was already conducting underway inspections in 18 major areas: anti-submarine warfare, aviation, auxiliary systems, communications, damage control, deck, electrical, environmental protection, information systems, medical facilities, main propulsion, navigation, occupational health, operations, supply, ventilation and weapons.
The inspection team included 38 uniformed technical inspectors with representatives from the fleet, NAVSEA and Space and Naval Warfare Systems Command. Numerous technical representatives from dozens of subcontractors stood by to rectify problems if they arose.
Hatches and doors were opened and closed, switches flipped on and off, lights and systems of all kinds checked out. Inspectors carrying microphones measured noise levels, and vibrations were measured while the ship ran through its propulsion paces.
Fit and finish of desks and lockers was checked; the cleanliness of all spaces was rated. Labels throughout the ship were checked for accuracy and spelling. Hundreds of pumps were checked. Breathing gear and life rafts got a close look. Radars and combat systems, sonars and solid waste shredders all came under INSURV’s discerning eye.
Inevitably, problems were discovered.
Possibly the most significant issue arose during the full-power astern trials, when the ship was required to back down at full power for one hour. Halfway through the run, the temperature of an engine lubrication oil pump rose to unacceptable levels, and the test was halted after about 40 minutes.
The problem was traced to an auxiliary seawater intake on the ship’s underside. Located forward of the propeller shafts, the intake was masked by cavitating bubbles as the ship moved astern. With no seawater to feed a heat exchanger to cool the lube oil pump, the temperature heated up.
It was an unusual problem that had not previously been encountered on the LPD 17-class ships, Stefany said, although it has appeared on other ships.
Richard Schenk, the shipbuilder’s vice president for test and trials, convened a late-night brainstorming session with experts in the wardroom to hear ideas about what caused the cavitation problem. The next day, he offered some thoughts about what happened.
“There was a heavier sea state” than on previous sea trials, he noted, with considerable wave-slapping on the square stern. The ship’s draft — how deep it lies in the water — was also a bit less than normal, possibly contributing to increased propeller cavitation.
Sea trials can be “very dynamic,” Schenk noted, with a variety of factors involved.
More testing and analysis, Stefany and Schenk said, would be needed before a final determination of the problem was reached.
Other issues during the trials, Mitchell said, included an oil seal leak on a reduction gear — “fixable with a new part” — a shaft seal leak that would be fixed before the Navy takes over, and an electrical generator problem that INSURV rated a “one-off, new-ship issue” that would be fixed shortly.
Inspectors also dinged the ship for relatively minor issues, such as cleanliness and fit-and-finish details.
Most of the ship’s trial items, however, turned out better. The combat systems ran through detect-to-engage drills with few problems, the trials team reported. Unlike the live-fire demonstrations on a new destroyer, an amphibious ship’s weapons are not usually fired during trials. Rather, simulations are held, and the ship’s 30mm guns and RAM missile launchers aren’t actually exercised until the Combat Systems Ship Qualifications Trials held sometime after the ship enters service.
Avondale, which built the San Antonio and most of the LPD 17s, is set to close at the end of 2013 after delivery this summer of Anchorage and of Somerset next year. The remaining ships in the class will be built at HII’s larger Ingalls shipyard in Pascagoula, Miss., as the company consolidates its Gulf Coast shipbuilding operations to meet shrinking Navy shipbuilding needs.
New ships conducting builder’s and acceptance sea trials are privately owned until they’re transferred to the Navy, and although sailors from the ship’s company are onboard to observe, civilians operate the ships. Shipbuilders from both of HII’s Gulf shipyards worked Anchorage throughout the trials — even handling all the messing duties — and a sense of the end of an era hung over some.
“I understand the economics,” said Bruce Knowles, the ship program manager in Avondale’s LPD program office. “The economy won’t support more than one yard here.”
As work on its last two ships has progressed, Avondale has been laying off workers. The workforce stands at about 2,800, down 1,000 from a year ago. The huge panel shop, where steel plates were cut and shaped to be turned into ship parts, is dark and silent, as are shops that handled pumps and pipes.
Knowles harkened to the Hurricane Katrina tragedy that struck New Orleans in 2005, when many Avondale workers lost their homes and were forced to commute great distances as they rebuilt. “These are some of the most resilient people I’ve ever met,” he observed.
Anchorage, he said, “is kind of a message we’re trying to send to God and country that we can still build the best damn ship.”
As the big ship headed back up the river on June 22, hopes were high that Anchorage had passed with proverbial flying colors, and there was talk of flying a broom from the mast, signifying a clean sweep of the trial items. But as it passed New Orleans and began to prepare for returning to the shipyard, frowns broke out as preliminary inspection scores were passed. While not bad, the scores weren’t as good as hoped for, and the broom remained in its locker.
Mitchell, who, as the Navy’s chief shipyard inspector on the Gulf Coast, worked with the shipbuilders to get Anchorage ready, was disappointed but unfazed.
“I think we’re on an improving trend,” he said. “There are no unfixable defects.”
INSURV President Wray, in his July 3 email, was positive in his evaluation of the ship. “In nearly all measures, LPD 23 Anchorage had a strong and successful trial,” he wrote. “She was ‘satisfactory’ in 14 of 18 equipment operating capabilities [EOCs, or key areas].
“First,” he wrote, “this is a typical trial scorecard, and second, it is a stronger performance than LPD 20, 21, or 22, who were satisfactory in between 11 and 13 of their 18 EOCs. Her demonstrations were not as strong as her predecessor, LPD 22 San Diego, primarily due to an issue in her seawater cooling system which manifested itself during a backing bell. We have not encountered this before; it is relatively minor; [NAVSEA] and the builder are working the problem and will have it resolved prior to delivery.”
“Without any hesitation,” Wray declared, “we recommended her acceptance to the chief of naval operations.”
Anchorage is expected to be delivered to the Navy in late July. After leaving the shipyard in the fall, it’ll head to its new home port of San Diego, and is expected to be commissioned in its namesake city sometime next year.
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