US Navy warships suffer serious structural defects

It would be pretty dicey for the US Navy to have destroyers that couldn't take the pounding of heavy seas across their bows but that seems to be the case.

The US Navy today admitted that many of its 51 Arleigh Burke-class (DDG) destroyers currently in service have serious structural defects, with repairs and bow-strengthening work to cost at least $62 million, according to a press statement from Jane's Navy International.

The USN has confirmed to Jane's ‘class-wide' structural buckling in the destroyers, with a source saying the impact of rough-sea slamming on the bow has led to the warping of main transverse bulkhead beams and some of the cribbing, Jane's said. According to a presentation on September 21 by Rear Admiral Kevin McCoy, the chief engineer at Naval Sea Systems Command's Naval Systems Engineering Directorate, the problem is widespread: structural analysis "indicated that the loads encountered by the damaged ships are significantly higher than those anticipated in original ship specifications. The higher loads are most likely due to bow slamming."

Weakened support beams were cut out, reinforced and replaced. In September, for example, one of the newest destroyers - USS Gridley (DDG 101) - was undergoing repairs for beam warping at BAE Systems' shipyard in San Diego, California. Jane's says even though some of the repairs have already been completed, the USN would not reveal the expected total costs. The Navy said: "Because the bow-strengthening work will be competitively bid during construction, post-shipyard availabilities, or future planned docking availabilities, costs are considered business and competition sensitive."

In a statement, Naval Sea Systems Command said: "This is a [Arleigh Burke] DDG 51-class issue, which will impact the entire class. The USN plans to implement bow strengthening on each DDG 51-class destroyer during construction, post-shipyard availabilities, or future planned docking availabilities."

Arleigh Burke-class destroyers are considered to be state-of-the-art warships. These destroyers are equipped with the Navy's AEGIS Combat System (ACS) integrated naval weapon system. When integrated with the ACS, the distributed Navy's Cooperative Engagement Capability (CEC) system that uses a complicated set of sensors and algorithms to let groups of ships and aircraft to link their radars to provide a composite picture of an attack area.

One Navy ship that won't be refurbished is the General Hoyt S. Vandenberg. The Cold War missile and NASA spacecraft tracking ship will soon be the second largest vessel ever intentionally sunk to become an artificial reef. But that's what it will become next spring when artificial reef experts Reefmakers will sink the 523-foot ship 140 feet of water off of Key West, Fla.

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