BATH, Maine — In 128 years of building warships for the Navy, Bath Iron Works has achieved innumerable mind-boggling accomplishments, but never anything like what happened at 2:04 a.m. on December 15.
That’s when the deckhouse of the shipyard’s newest project, the DDG 1000 Zumwalt-class destroyer, first made contact with the rest of the next-generation warship. Hoisting the 900-ton deckhouse 89 feet in the air shattered the shipyard’s previous heaviest lift by more than double.
“I’d say there was a sigh of relief across the shipyard,” said Bruce Gadaree, who is responsible for heavy lifts at BIW. “There were probably a lot of group hugs going around.”
For travelers observing the shipyard as they crossed the Kennebec River on the Sagadahoc Bridge, the scene probably wasn’t worth an extra glance. Even for employees inside the shipyard, many of whom had been working for 40 hours straight when the massive deckhouse finally touched down, the milestone was reached so slowly that it was barely perceptible.
While lifting something — even when its weight approaches 1.8 million pounds — may seem like a pretty straightforward operation, it isn’t. According to Cmdr. Brian Metcalf, the Navy’s on-site DDG 1000 program manager at BIW, the lift was a feat on a scale that has happened precious few times in the history of American shipbuilding, and probably never before in the construction of sea-surface combatants.
Ingalls Shipbuilding in Gulfport, Miss., built the 155-foot-long, 60-foot-high deckhouse, which is made of composites and includes the ship’s bridge, command center and battle room. It was then shipped by barge to Bath Iron Works. The barge and deckhouse were lifted from the water by BIW’s huge dry dock and painstakingly moved to the solid ground of BIW’s Land-Level Transfer Facility. That’s when the records started falling.
Using two of BIW’s 300-ton capacity cranes and two additional 400-ton cranes provided by Reed & Reed Inc. of Woolwich, the deckhouse was lifted straight up, 89 feet in the air, and held there for hours. Garadee said more than 18 months of planning led up to that lift. To accomplish it, the deckhouse, which weighs more than six diesel locomotives, was specially designed to withstand its own weight at the 12 places where super-strong nylon straps connected it to the cranes above. The downward force on the cranes was so intense the ground beneath them was reinforced to distribute the load.
The barge was moved out of the way and workers prepared to break another record: moving the hull of the more than 12,000-ton ship underneath the deckhouse.
BIW is the lead design and construction yard for the DDG 1000, but is relying on Ingalls, which for years had been its chief competitor, to construct the composite portions of the ship, such as the deckhouse and a helicopter hangar which was put into place early last year.
Slowly, the four cranes lowered the deckhouse onto the ship. One might expect to hear groans, creaks and pops as machinery fought so hard against gravity, but Garadee said it happened almost silently, testament to the sound design and construction of the deckhouse.
With the deckhouse atop the hull, another record fell as the ship and deckhouse were moved back from beneath the cranes. At 13,000 tons, the structure weighs as much as 91 diesel locomotives or 5,200 full-sized Ford pickup trucks.
Todd Estes, who is responsible for acquiring materials and components for the DDG 1000 for Bath Iron Works, said last month’s project is another reminder of the world-class shipbuilders working there.
“It’s one of our biggest engineering achievements and one of the most complex,” said Estes. “Show me someone else in the country where anything like this is happening. It’s happening right here in Maine.”
Brent West, BIW’s DDG 1000 program manager, said the shipyard can hardly afford to rest on its laurels. With two more of the next-generation warships under construction, another deckhouse is due in Bath a year from now. He expects BIW’s 5,200-person workforce to once again achieve what in years past might have seemed impossible.
“This is a team sport,” he said. “There’s no one individual involved in these projects who is more important as another.”