An image of the U.S. Navy’s Virginia class submarine, the USS Mississippi, appeared on the cover of Honolulu’s Star Advertiser earlier this week, as the submarine returned to its home port at Pearl Harbor, Hawaii. Although the image itself is a pleasant one, depicting the massive nuclear submarine juxtaposed against the serene landscape of the Hawaiian Islands, a closer inspection betrays a serious problem facing America’s fleet of tactical submarines: the sound proofing material is peeling off of the hull of the ship.
Virginia class submarines are the most advanced in the world, boasting a nuclear power source, Tomahawk cruise missiles, and MK48 torpedoes. These submarines are tasked with hunting down and targeting enemy submarines and surface vessels, as well as force projection onto land-based theaters through its supply of cruise missiles. The submarines are stealthy killers with enough firepower to be considered formidable opponents for anything else the world has to offer… but a failure in the glue used to adhere the sound proofing coating that keeps these submarines difficult to detect may be putting our submarine force at risk.
The problem was first identified by the Navy in 2010, and they promptly announced that they had a solution they were developing that would keep the sound proof coating on the hulls of their submarines. Two years later, the USS Mississippi was commissioned, and one would think that a solution would have already been well in hand by that time – but the photograph posted in the Star Advertiser clearly shows that the material has been coming off the Mississippi in large chunks.
While underwater, submarines face two sound-based challenges when keeping themselves hidden from enemy ships. The first is the submarine’s internal sound levels, which can carry through the water and be detected by submarine detection equipment. The second is sonar, which like radar, works by transmitting a signal through the water, which bounces back when it comes into contact with things like the hull of a submarine. In order to address each of these challenges, the Navy began using anechoic coatings on all of its submarines designed to absorb sonar waves that come into contact with the ship, as well as to insulate the ship from allowing sounds produced by the submarine itself to be carried through the hull and into the water.