Yamato class battleship

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General characteristics per Plan No. A-104F6
Yamato on trials, 1941
Displacement:	Trial displacement of 68,200 British tons (69,294 tonnes) Standard displacement of 64,000 British tons (65,027 tonnes) Maximum displacement of 72,000 British tons (72,820 tonnes)
Length:	256 m (839.88 ft) at water-line 263 m (862.85 ft) overall
Beam:	38.9 m (130.90 ft)
Draught:	10.4 m (34.12 ft)
Propulsion:	12 Kanpon boilers, driving 4 steam turbines 150,000 shp (110 MW) Four 3-bladed propellers, 6.0 m (19.7 ft) diameter
Speed:	27 knots (50 km/h)
Range:	7,200 nautical miles (13,334 km) at 16 knots (30 km/h)
Complement:	2,750
Armor:	650 mm on face of turrets 410 mm side armor, inclined 20 degrees 200 mm armored deck
Armament:	9 x 46 cm (18.1 inch) (3 × 3) 12 × 15.5 cm (6.1 inch) (4 × 3) 12 × 12.7 cm (6 × 2) 24 × 25 mm AA (8 × 3) 4 × 13 mm AA (2 × 2)
Aircraft:	7, 2 catapults

The Yamato class battleships (大和型) of the Imperial Japanese Navy (IJN) were the largest naval vessels of World War II and were the largest, heaviest battleships ever constructed, displacing 65,027 metric tons and armed with nine 46 cm main guns.

1 Design and construction
2 Deployment
3 References
4 External links

[edit] Design and construction

Japanese naval strategy after World War I included plans for the construction of a fleet powerful enough to intimidate likely opponents, in particular the United States Navy. Although these plans were curtailed by Japan's participation in the Washington Naval Treaty of 1922, the IJN continued technical studies and by 1933 had concluded that any new class of battleship would feature main armament of 46 cm.

International sanctions in 1934 led Japan to announce its withdrawal from the Washington Treaty, by which time the IJN was already at work on the design for a super-battleship that would be known as the Yamato class.

Preliminary studies called for a ship featuring a main battery comprising at least eight 46 cm guns, a secondary battery comprising four turrets armed with either triple 15.3 cm or double 20 cm guns, defensive armor capable of withstanding a bombardment equivalent to the ship's own main battery from a range of 20,000 to 35,000 meters, a top speed of 30 knots, and a cruising range of 8,000 nautical miles (14,800 km) at a speed of 18 knots.

The earliest version of Plan No. A-140 ("A" indicating "battleship" and "140" indicating that this was the 140th warship designed by the IJN) was completed in March 1935, showing a ship 294 m long at the waterline with a 41.2 m beam, a 10.4 m draught, and a trial displacement of 69,500 British tons. One notable feature of this and other early designs is that all three turrets of the main battery are concentrated forward of the ship's superstructure.

In all, 22 different preliminary designs were drawn up during the period lasting until October 1935, when Plan Nos. A-140F3 and A-140F4 were issued.

Refinement of the design continued as detailed studies were made, and testing of models in a model basin led to the adoption of a semitransom stern and a bulbous bow, which reduced hull resistance by 8%, and when Plan No. A-140F5 was issued in July 1936, it called for a ship 253 m long at the waterline with a 38.9 m beam, a 10.4 m draught, and a trial displacement of 65,200 British tons.

Plan No. A-140F6 was finalized at the end of March 1937, and a construction order issued at the begininng of August to the Kure Naval Dockyards, where a construction dock was deepened, gantry crane capacity increased to 100 metric tonnes, and part of the dock roofed over to prevent observation of work. Construction began on 4 November 1937 and continued for nearly three years. Yamato was launched on 8 August 1940 and commissioned on 16 December 1941.

Construction of the second hull began six months later at the Mitsubishi Nagasaki Shipyard, where Musashi was launched on 1 November 1940 and commissioned 5 August 1942.

Construction of Hull Number 110 began in May 1940 at the Yokosuka Naval Dockyards and was not expected to be completed until 1945. Following devastation of Japan's carrier forces at the Battle of Midway, however, the decision was made to convert this hull to an aircraft carrier and expedite its completion. Shinano was launched 8 October 1944 and commissioned the following 19 November.

A total of five Yamato class battleships were planned. Hull Number 111 was scrapped in 1943 when only 30% complete, and a proposed fifth hull, Number 797, proposed in the 1942 5th Supplementary Program, was never ordered.

Plans for a "super Yamato" class, with 50.8 cm guns, provisionally designated as Hull Number 798 and Hull Number 799, were abandoned in 1942.

[edit] Deployment

Like their German counterparts, Bismarck and Tirpitz, Yamato and Musashi made little direct impact during the war. Neither engaged any Allied battleships during the war, and were instead both sunk by the bane of capital warships: overwhelming air power. Musashi was sunk by repeated aerial attack during the Battle of Leyte Gulf on October 24, 1944. After being hit by an estimated 17 torpedoes and 20 bombs, she went down with 1,700 of her 2,400 man crew.

The end of Yamato was even less glorious. Having seen little action during the previous four years (She served as Yamamoto's flagship during the Midway operation, as well as the action off Samar on 25 October 1944) she was sent on a virtual suicide mission against the U.S. Navy forces massing for the attack on Okinawa. On April 7, 1945 she was hit by successive waves of US carrier based aircraft and sank after absorbing 5 - 10 bombs and at least 10 torpedo hits. Less than 300 out of 3,400 crew onboard survived.