9/4/2009
NEWS BRIEFS
Bolt Problem Delays Submarine Commission

Improperly installed bolts on weapons-handling systems will delay the commission of the U.S.S. New Mexico, the Navy reports.

The New Mexico was reportedly going to be delivered this month, but reworking the fastener issues on the submarine will push the delivery back until at least November.

The New Mexico was one of four U.S. Navy Virginia-class submarines to be sidelined by the bolt issue. The others include the USS North Carolina, USS Missouri and USS California.

The Navy has scheduled the commissioning for early 2010.

Workers at Northrop Grumman’s Newport News shipyard reportedly mishandled the fasteners that hold together tracks on which weapons are moved in the sub’s torpedo room.

“During the final alignment of the forward and aft weapon cradle tracks aboard the Missouri, several bolts, bolt holes and fasteners were found that did not meet specifications. Specifically, the shipbuilders have found improperly drilled and machined bolt holes, bolts that had been improperly machined, and fasteners that were not installed and tightened properly,” according to a written statement from Naval Sea Systems Command (NAVSEA).

The application of nonspecification bolts, bolt holes and fasteners “could result in a misalignment of the weapons-handling equipment that could prevent the movement of weapon cradles within the torpedo room, and could compromise the integrity of the weapons handling system in a shock event,” according to a NAVSEA statement quoted in the Navy Times.

Inappropriate use of the fastener adhesive Loctite is also reportedly part of the issue.

Northrop Grumman described the problem as including “use of the incorrect grade of Loctite; close tolerance bolts that were modified without the proper use of appropriate technical direction (certain shanks tapered, thread ends cut short); close tolerance bolts that did not meet the diametrical clearance requirements for the respective hole; truss tapped holes that were damaged and nonconforming threads,” the Navy Times reports.

Cost or repair time estimates on the four affected submarines have not been made public. ©2009 GlobalFastenerNews.com