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The ''Nevada''-class battleships were the United States Navy's first battleship design equipped with triple gun turrets (the would be the last to carry twin turrets, armed with dual-mounted 16-inch guns), as well as introducing the "all or nothing" armor scheme in American capital ship design, in which protection of vital areas was optimized against heavy caliber guns, leaving other parts of the ship essentially unprotected. The ''Nevada''s also introduced completely oil-fired propulsion. In armament, armor, and propulsion the ''Nevada'' class represented a considerable evolution in battleship design and, in being designed specifically to fight at extreme gunnery ranges, was actually well ahead of its time. They would be followed by the s. Two ships of this class were constructed: USS ''Nevada'' (BB-36) and USS ''Oklahoma'' (BB-37). The ''Nevada''s were the first Standard-type battleships produced by the U.S. Navy〔 Along with the , , and classes, the standard type offered a battle line of vessels homogeneous in long-range gunnery, speed, tactical radius and damage control. The essential characteristics of the standard type were oil fuel, "all or nothing" armor, the arrangement of the main battery into four turrets, and significant deck armor providing protection against shells fired from long range. This combination of features made the ''Nevada''s the prototype of the modern battleship. For example, the protection of the standard class battleships was not significantly revised after the Battle of Jutland, while other Navies tended to have different pre- and post-Jutland designs. Active in the Atlantic Ocean before and during World War I, the ''Nevada''s were deployed to protect Allied supply lines in the European war zone in 1918. Their service continued after the "Great War", though by the early 1920s they were the oldest of the main Battle Fleet units. Both were extensively modernized between 1927 and 1929. ''Oklahoma'' was sunk during the attack on Pearl Harbor in 1941 and was a total loss. ''Nevada'' beached herself during this raid to prevent blocking the harbor entrance after receiving damage, and was salvaged and modernized. She provided gunfire support for amphibious operations in the European and Pacific theaters, which included shelling German shore batteries on D-Day along with and . Considered too old at the end of World War II to be kept in active service, ''Nevada'' was used as a target ship for nuclear and conventional weapons from 1946 to 1948, proving that her protection scheme was sound as she remained afloat for further target use after nuclear weapons tests in Operation Crossroads. ==Design== With these ships the U.S. Navy developed a template known as the Standard-type battleship that it would use until the Washington Naval Treaty brought an end to dreadnought construction in 1922. Its essentials were consistent size and speed, oil fuel instead of coal, and a reversion to the superfiring mounting of heavy guns in four turrets that was used in the to keep the citadel compact. The decision to mount triple gun turrets proved controversial. Naval officers and engineers warned of "putting too many eggs in one basket"; that a lucky hit could disable more of the main guns than if they were carried in twin turrets and leave a ship at a disadvantage in battle. Shipbuilders warned that triple turrets could affect a ship's stability adversely because of their greater weight, especially when raised in a superfiring mounting. However, the Navy's Bureau of Construction and Repair (C&R), which designed the ''Nevada''s, considered triple turrets necessary to save space and weight, keep the citadel at a reasonable size, and maximize the armor protection accordingly. It also eliminated the challenges of steam lines running through main gun magazines and ineffective placement of heavy guns, as occurred with midships turrets in previous classes. The Navy would use triple turrets in almost all of its subsequent battleship designs. The ''Nevada''s were also the first U.S. battleships to use the "all or nothing" principle of armor protection, also known as "raft body" armor. Previous battleships had armor of varying thickness depending on the importance of the area it was protecting. On the ''Nevada''s, armored surfaces were limited to a minimum but were given the maximum thickness possible to give the most protection to critical areas such as magazines, engines and command areas and to ensure the maintenance of buoyancy. The ship's overall design, especially the triple turrets, was to reduce the length of the protected portion of the ship. Heavy deck armor was emphasized to guard against plunging fire. Citadel armor was omitted entirely in the thought that medium-heavy armor could actually be a detriment, since it could no longer afford protection against a direct hit and potentially cause enemy shells to explode and cause further damage. In short, the ''Nevadas'' were designed specifically to fight at the extreme ranges expected by gunnery experts. In that sense, they were well ahead of their time, as the Battle of Jutland in 1916 would show. While other navies distinguished between their pre- and post-Jutland capital ship designs, the U.S. Navy did not feel so compelled. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Nevada-class battleship」の詳細全文を読む スポンサード リンク
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