The Montana-class battleships were planned as successors of the Iowa class for the United States Navy, to be slower but larger, better armored, and with superior firepower. Five were approved for construction during World War II, but changes in wartime building priorities resulted in their cancellation in favor of continuing production of Essex-class aircraft carriers and Iowa-class battleships before any Montana-class keels were laid.
USS Washington (BB-47), a Colorado-class battleship, was the second ship of the United States Navy named in honor of the 42nd state. Her keel was laid down on 30 June 1919, at Camden, New Jersey, by the New York Shipbuilding Corporation. She was launched on 1 September 1921, sponsored by Miss Jean Summers, the daughter of Congressman John W. Summers of Washington.
The Iowa class was a class of six fast battleships ordered by the United States Navy in 1939 and 1940. They were initially intended to intercept fast capital ships such as the Japanese Kongō class and serve as the "fast wing" of the U.S. battle line. The Iowa class was designed to meet the Second London Naval Treaty's "escalator clause" limit of 45,000-long-ton (45,700 t) standard displacement. Beginning in August 1942, four vessels, Iowa, New Jersey, Missouri, and Wisconsin, were completed; two more, Illinois and Kentucky, were laid down but canceled in 1945 and 1958, respectively, before completion, and both hulls were scrapped in 1958–1959.
The 16"/50 caliber Mark 7 – United States Naval Gun is the main armament of the Iowa-class battleships and was the planned main armament of the cancelled Montana-class battleship.
The North Carolina class were a pair of fast battleships, North Carolina and Washington, built for the United States Navy in the late 1930s and early 1940s.
The Colorado-class battleships were a group of four United States Navy super-dreadnoughts, the last of its pre-Treaty battleships. Designed during World War I, their construction overlapped the end of that conflict and continued in its immediate aftermath. Though all four keels were laid, only three ships entered service: Colorado, Maryland, and West Virginia. Washington was over 75% completed when she was canceled under the terms of the Washington Naval Treaty in 1922. As such, the 16" gun Colorado-class ships were the last and most powerful battleships built by the U.S. Navy until the North Carolina class entered service on the eve of World War II.
The Alaska-class were six large cruisers ordered before World War II for the United States Navy (USN), of which only two were completed and saw service late in the war. The USN designation for the ships of this class was 'large cruiser' (CB), a designation unique to the Alaska-class, and the majority of leading reference works consider them as such. However, various other works have alternately described these ships as battlecruisers despite the US Navy having never classified them as such, and having actively discouraged the use of the term in describing the class. The Alaskas were all named after territories or insular areas of the United States, signifying their intermediate status between larger battleships and smaller heavy and light cruisers.
The Florida-class battleships of the United States Navy comprised two ships: Florida and Utah. Launched in 1910 and 1909 respectively and commissioned in 1911, they were slightly larger than the preceding Delaware class design but were otherwise very similar. This was the first US battleship class in which all ships received steam turbine engines. In the previous Delaware-class, North Dakota received steam turbine propulsion as an experiment while Delaware retained triple-expansion engines.
The Delaware-class battleships of the United States Navy were the second class of American dreadnoughts. With this class, the 16,000 long tons (16,257 t) limit imposed on capital ships by the United States Congress was waived, which allowed designers at the Navy's Bureau of Construction and Repair to correct what they considered flaws in the preceding South Carolina class and produce ships not only more powerful but also more effective and rounded overall. Launched in 1909, these ships became the first in US naval history to exceed 20,000 long tons (20,321 t).
The N3 class was a dreadnought battleship class designed for the Royal Navy after World War I, incorporating lessons learned from that conflict. They were similar in design to the G3-class battlecruiser, but had larger guns and thicker armour. They were never ordered due to signing of the Washington Naval Treaty in 1922, which limited the size and armament of battleships to 35,000 long tons (36,000 t) and guns no bigger than 16 inches (406 mm).
The South Dakota class was a group of four fast battleships built by the United States Navy. They were the second class of battleships to be named after the 40th state; the first were designed in the 1920s and canceled under the terms of the Washington Naval Treaty. Four ships comprised the class: South Dakota, Indiana, Massachusetts, and Alabama. They were designed to the same treaty standard displacement limit of 35,000 long tons (35,600 t) as the preceding North Carolina class and had the same main battery of nine 16"/45 caliber Mark 6 guns in three-gun turrets, but were more compact and better protected. The ships can be visually distinguished from the earlier vessels by their single funnel, compared to twin funnels in the North Carolinas.
The first South Dakota class was a group of six battleships that were laid down in 1920 for the U.S. Navy, but were never completed; designed to achieve 23 knots, they represented an attempt to catch up with the increasing fleet speeds of its main rivals, the British Royal Navy and Imperial Japanese Navy.
The BL 14-inch Mk VII naval gun was a breech loading (BL) gun designed for the battleships of the Royal Navy in the late 1930s. This gun armed the King George V-class battleships during the Second World War.
The Iowa-class battleships are the most heavily armed warships the United States Navy has ever put to sea, due to the continual development of their onboard weaponry. The first Iowa-class ship was laid down in June 1940; in their World War II configuration, each of the Iowa-class battleships had a main battery of 16-inch (406 mm) guns that could hit targets nearly 20 statute miles (32 km) away with a variety of artillery shells designed for anti-ship or bombardment work. The secondary battery of 5-inch (127 mm) guns could hit targets nearly 9 statute miles (14 km) away with solid projectiles or proximity fuzed shells, and was effective in an anti-aircraft role as well. Each of the four battleships carried a wide array of 20 mm and 40 mm anti-aircraft guns for defense against enemy aircraft.
The 6-inch/47 caliber Mark 16 gun was used in the main batteries of several pre-war and World War II US Navy light cruisers. They were primarily mounted in triple turrets and used against surface targets. The Mark 16DP gun was a dual purpose fitting of the Mark 16 for use against aircraft as well as surface ships. It was installed in the post-war Worcester-class light cruisers and the anti-aircraft gunnery training ship Mississippi.
The 14-inch/45 caliber gun,, whose variations were known initially as the Mark 1, 2, 3, and 5, and, when upgraded in the 1930s, were redesignated as the Mark 8, 9, 10, and 12. They were the first 14-inch (356 mm) guns to be employed by the United States Navy. The 14-inch/45 caliber guns were installed as the primary armament aboard all of the United States Navy's New York-class, Nevada-class, and Pennsylvania-class battleships. The gun also saw service in the British Royal Navy, where it was designated BL 14 inch gun Mk II.
The 14"/50 caliber gun was a naval gun mounted on New Mexico and Tennessee-class battleships. These ships also featured the first "three-gun" turrets, meaning that each gun in each turret could be "individually sleeved" to elevate separately. The 14"/50 caliber guns were designated as Mark 4 and 6, with later versions known as Mark 7, 11, and B. These guns were more powerful than the main gun mounted on the previous three classes of US battleships, the 14"/45 caliber gun.
The 12"/50 caliber gun Mark 8 was a US naval gun mounted on the Alaska-class cruiser. The gun, like the "large cruiser" that mounted it, was intended to fill the gap between US "heavy cruisers" (6-8") and US battleships (14-16"). The name describes the size of the shells, 12 inches in diameter, and the length of the bore in calibers.
The 12″/45 caliber Mark 5 gun was an American naval gun that first entered service in 1906. Initially designed for use with the Connecticut-class of pre-dreadnought battleships, the Mark 5 continued in service aboard the first generation of American dreadnoughts.
The 16"/50 caliber Mark 2 gun and the near-identical Mark 3 were guns originally designed and built for the United States Navy as the main armament for the South Dakota-class battleships and Lexington-class battlecruisers. The successors to the 16"/45 caliber gun Mark I gun, they were at the time among the heaviest guns built for use as naval artillery.
