US Navy The Zumwalt-class destroyers are a class of United States Navy destroyers designed as multi-mission ships with a focus on land attack. The class is a scaled-back project that emerged after funding cuts to the larger DD-21 vessel program. The program was previously known as the "DD(X)". The class is multi-role and designed for surface warfare, anti-aircraft, and naval fire support. They take the place of battleships in filling the former congressional mandate for naval fire support,[8] though the requirement was reduced to allow them to fill this role. The vessels' appearance has been compared to that of the historic ironclad warship.[9] The class has a low radar profile; an integrated power system, which can send electricity to the electric drive motors or weapons, which may someday include a railgun[10] or free-electron lasers;[11] total ship computing environment infrastructure, serving as the ship's primary LAN and as the hardware-independent platform for all of the ship's software ensembles; automated fire-fighting systems and automated piping rupture isolation. The class is designed to require a smaller crew and be less expensive to operate than comparable warships. It will have a wave-piercing tumblehome hull form whose sides slope inward above the waterline. This will reduce the radar cross-section, returning much less energy than a more hard-angled hull form. As of January 2009, the Government Accountability Office (GAO) found that only four out of 12 of the critical technologies were mature.[12] The lead ship will be named Zumwalt for Admiral Elmo Zumwalt, and carries the hull number DDG-1000. Originally 32 ships were planned, with the $9.6 billion research and development costs spread across the class, but as the quantity was reduced to 10, then 3, the cost-per-ship increased dramatically.[13][14] The cost increase caused the U.S. Navy to identify the program as being in breach of the Nunn--McCurdy Amendment on 1 February 2010.[15][16] Stealth[edit] Despite being 40% larger than an Arleigh Burke-class destroyer the radar signature is more akin to a fishing boat and sound levels are compared to the Los Angeles-class submarines. The tumblehome hull reduces radar return and the composite material deckhouse also has a low radar return. Water sleeting along the sides, along with passive cool air induction in the mack reduces thermal emissions.[42] The U.S. Navy solicited bids for a lower cost steel deckhouse as an option for DDG-1002, the last Zumwalt destroyer in January 2013.[43][44][45] On 2 August 2013, the US Navy announced it was awarding a $212 million contract to General Dynamics Bath Iron Works to build a steel deckhouse for destroyer Lyndon B. Johnson (DDG-1002).[45] The United States Navy (USN) is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. It is larger than the next 13 largest navies combined in terms of battle fleet tonnage, according to one estimate.[5][6] The U.S. Navy also has the world's largest carrier fleet, with 10 in service, one under construction (two planned), and two in reserve. The service has 317,054 personnel on active duty and 109,671 in the Navy Reserve. It operates 283 ships in active service and more than 3,700 aircraft.[3] The navy traces its origins to the Continental Navy, which was established during the American Revolutionary War and was essentially disbanded as a separate entity shortly thereafter. It played a major role in the American Civil War by blockading the Confederacy and seizing control of its rivers. It played the central role in the World War II defeat of Japan. The 21st century United States Navy maintains a sizable global presence, deploying in such areas as East Asia, the Mediterranean, and the Middle East. It is a blue-water navy with the ability to project force onto the littoral regions of the world, engage in forward areas during peacetime, and rapidly respond to regional crises, making it an active player in U.S. foreign and defense policy. The Navy is administratively managed by the Department of the Navy, which is headed by the civilian Secretary of the Navy. The Department of the Navy is itself a division of the Department of Defense, which is headed by the Secretary of Defense. The Chief of Naval Operations is a four-star admiral and the senior naval officer of the Department of the Navy.[7] However, the CNO may not be the highest ranking naval officer in the armed forces if the Chairman or the Vice Chairman of the Joint Chiefs of Staff are Navy officers, who by law, outrank the CNO. For other uses of "US", "USA", and "United States", see US (disambiguation), USA (disambiguation), and United States (disambiguation). United States of America The United States of America (USA), commonly referred to as the United States (US), America, or simply the States, is a federal republic[10][11] consisting of 50 states, 16 territories, and a federal distr

• published: 11 Jan 2014
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