Transplant complete, attack sub floats again - Navy News | News from Afghanistan & Iraq - Navy Times

Transplant complete, attack sub floats again

More than three years after a devastating underwater crash killed one sailor, injured 100 more and crushed the bow of the fast-attack submarine San Francisco, the ship has returned to the water after a first-of-its kind overhaul.

In the maritime equivalent of a major organ transplant, workers at Puget Sound Naval Shipyard, Wash., amputated more than 1 million pounds’ worth of the bow section of the decommissioned attack sub Honolulu and grafted it onto the ailing San Francisco.

“The engineering and production teams proceeded to manipulate the mammoth structure with orchestrated precision,” according to an announcement from Naval Sea Systems Command. “In some areas, the bow of this massive structure was moved to within 1/16 of an inch of the original structure.”

With the surgery complete, the San Francisco floated off its dry dock for the first time Oct. 10. The ship has been in the yard since December 2006.

The systems transferred from the Honolulu — a newer Los Angeles-class sibling commissioned in 1985, four years after the San Francisco — included its active sonar sphere and its forward ballast tanks.

Although the Honolulu is four years younger than the San Francisco, the older sub’s nuclear reactor had been refueled three years before the accident at a cost of roughly $170 million.

The Honolulu was scheduled to be decommissioned in 2006 even before Navy planners decided to use its bow section on the older sub.

Navy engineers determined it would be cheaper to transplant the Honolulu’s forward equipment to the San Francisco, for an estimated $79 million, than it would have been to refuel the Honolulu, for another estimated $170 million, if it were kept in commission.

The San Francisco crashed into an undersea mountain Jan. 8, 2005, suffering damage so severe that the warship almost sunk. The ship struggled to Guam, and after temporary repairs, the ship sailed 5,600 nautical miles to Puget Sound on the surface, the longest trip a U.S. submarine has made without submerging.

Although the San Francisco is the first submarine to get another submarine’s bow, the procedure is common with surface ships. In 1956, for example, the battleship Wisconsin collided with a destroyer in heavy weather off Norfolk. To repair it, Navy engineers sliced the bow off one of the two unfinished Iowa-class battleships, the Kentucky, and replaced the Wisconsin’s original bow.