was the lead ship of the two dreadnought battleships built for the Imperial Japanese Navy. Launched in 1914 and commissioned in 1915, she initially patrolled off the coast of China, playing no part in World War I. In 1923, she assisted survivors of the Great Kantō earthquake.
Fusō was modernized in 1930–1935 and again in 1937–1941, with improvements to her armor and propulsion machinery and a rebuilt superstructure in the pagoda mast style. Nonetheless, she was still hampered by slow speed and outclassed by newer Japanese battleships at the beginning of World War II, and played auxiliary roles for most of the war.
Fusō was part of Vice-Admiral Shōji Nishimura's Southern Force at the Battle of Leyte Gulf. She was sunk in the early hours of 25 October 1944 by torpedoes and naval gunfire during the Battle of Surigao Strait. Some reports claimed Fusō broke in half, and that both halves remained afloat and burning for an hour; according to survivors' accounts, however, the ship sank after 40 minutes of flooding and caught fire when her fuel bunkers spilled open. Of the few dozen crewmen who escaped, only 10 survived to return to Japan.
Description
The ship had a length of between perpendiculars and overall. She had a beam of and a draft of .Gardiner & Gray, p. 229 Fusō displaced at standard load and at full load.Jentschura, Jung and Mickel, p. 25 Her crew consisted of 1,198 officers and enlisted men in 1915 and 1,396 in 1935. During World War II, the crew probably totalled around 1,800–1,900 men.Skulski, p. 30
During the ship's first modernization during 1930–1933, her forward superstructure was enlarged with multiple platforms added to her tripod foremast. Her rear superstructure was rebuilt to accommodate mounts for anti-aircraft (AA) guns and additional fire-control directors. Fusō was also given torpedo bulges to improve her underwater protection and to compensate for the weight of the additional armor and equipment. During the second phase of her first reconstruction in 1934–1935, Fusōs torpedo bulge was enlarged and her stern was lengthened by . These changes increased her overall length to , her beam to and her draft to . Her displacement increased by nearly to at deep load.Skulski, pp. 11, 29
Propulsion The ship had two sets of Brown-Curtis direct-drive steam turbines, each of which drove two propeller shafts. The turbines were designed to produce a total of , using steam provided by 24 Miyahara-type water-tube boilers, each of which consumed a mixture of coal and oil. Fusō had a stowage capacity of of coal and of fuel oil,Skulski, p. 17 giving her a range of at a speed of . The ship exceeded her design speed of during her sea trials, reaching at .Jentschura, Jung and Mickel, pp. 25–26
During her first modernization, the Miyahara boilers were replaced by six new Kampon oil-fired boilers fitted in the former aft boiler room, and the forward funnel was removed. The Brown-Curtis turbines were replaced by four geared Kanpon turbines with a designed output of . During her 1933 trials, Fusō reached a top speed of from . The fuel storage of the ship was increased to a total of of fuel oil that gave her a range of at a speed of .
Armament
The twelve 45-caliber 14-inch guns of Fusō were mounted in six twin-gun turrets, numbered one through six from front to rear, each with an elevation range of −5 to +30 degrees.Skulski, p. 18 The turrets were arranged in an uncommon 2-1-1-2 style with superfiring pairs of turrets fore and aft; the middle turrets were not superfiring, and had a funnel between them. The main guns and their turrets were modernized during the ship's 1930 reconstruction; the elevation of the main guns was increased to +43 degrees, increasing their maximum range from . Initially, the guns could fire at a rate of 1.5 rounds per minute, and this was also improved during her first modernization.Skulski, p. 18 The orientation of Turret No. 3 was reversed during the modernization; it now faced forward.Chesneau, p. 171
Originally, Fusō was fitted with a secondary armament of sixteen 50-caliber six-inch 41st Year Type guns mounted in casemates on the upper sides of the hull. The gun had a maximum range of Skulski, p. 20 and fired at a rate of up to six shots per minute.Campbell, p. 189 She was fitted with five 40-caliber three-inch (76 mm) AA guns in 1918. The high-angle guns were in single mounts on both sides of the forward superstructure and both sides of the second funnel, as well as on the port side of the aft superstructure. These guns had a maximum elevation of +75 degrees, and could fire a shell at a rate of 13 to 20 rounds per minute to a maximum height of .Campbell, p. 198 The ship was also fitted with six submerged torpedo tubes, three on each broadside.Skulski, p. 30
During the first phase of Fusōs modernization of the early 1930s, all five three-inch guns were removed and replaced with eight 40-caliber 127-millimeter dual-purpose guns, fitted on both sides of the fore and aft superstructures in four twin-gun mounts.Skulski, p. 21 When firing at surface targets, the guns had a range of ; they had a maximum ceiling of at their maximum elevation of +90 degrees. Their maximum rate of fire was 14 rounds a minute, but their sustained rate of fire was around eight rounds per minute.Campbell, pp. 192–93 At this time, the ship was also provided with four quadruple mounts for the license-built Type 93 13.2 mm machine guns, two on the pagoda mast and one on each side of the funnel. The maximum range of these guns was , but the effective range against aircraft was only . The cyclic rate was adjustable between 425 and 475 rounds per minute, but the need to change 30-round magazines reduced the effective rate to 250 rounds per minute.Skulski, pp. 21–22
The improvements made during the first reconstruction increased Fusōs draft by , soaking the two foremost six-inch guns, so they were removed during the first phase of the ship's second modernization in 1937 and 1938.Skulski, pp. 20, 30 During this same phase, the Type 93 machine guns were replaced by eight 25 mm Type 96 light AA guns in twin-gun mounts. Four of these mounts were fitted on the forward superstructure, one on each side of the funnel and two on the rear superstructure. This was the standard Japanese light AA gun during World War II, but it suffered from severe design shortcomings that rendered it a largely ineffective weapon. According to historian Mark Stille, the twin and triple mounts "lacked sufficient speed in train or elevation; the gun sights were unable to handle fast targets; the gun exhibited excessive vibration; the magazine was too small, and, finally, the gun produced excessive muzzle blast".Stille, p. 11 The configuration of the AA guns varied significantly; in July 1943, 17 single and two twin-mounts were added for a total of 37.Stille, p. 23 In July 1944, the ship was fitted with additional AA guns: 23 single, six twin and eight triple-mounts, for a total of 95 in her final configuration.Skulski, p. 22 These guns had an effective range of , and an effective ceiling of at an elevation of +85 degrees. The maximum effective rate of fire was only between 110 and 120 rounds per minute because of the frequent need to change the fifteen-round magazines.Campbell, p. 200
Armor The ship's waterline armor belt was thick; below it was a strake of armor. The deck armor ranged in thickness from . The turrets were protected with an armor thickness of on the face, on the sides, and on the roof. The barbettes of the turrets were protected by armor 305 mm thick, while the casemates of the 152 mm guns were protected by 152 mm armor plates. The sides of the conning tower were thick. The vessel contained 737 watertight compartments (574 underneath the armor deck, 163 above) to preserve buoyancy in the event of battle damage.Skulski, pp. 16, 101, 163
During her first reconstruction Fusōs armor was substantially upgraded. The deck armor was increased to a maximum thickness of . A longitudinal bulkhead of of high-tensile steel was added to improve underwater protection.Skulski, pp. 16, 101
Aircraft Fusō was briefly fitted with an aircraft flying-off platform on Turret No. 2 in 1924. During the first phase of her first modernization, a catapult was fitted on the roof of Turret No. 3 and the ship was equipped to operate three floatplanes, although no hangar was provided. The initial Nakajima E4N2 biplanes were replaced by Nakajima E8N2 biplanes in 1938. Fusōs ability to operate her aircraft was greatly improved during the second phase of her second modernization in 1940–41 when the aircraft handling equipment was moved to the stern and a new catapult was installed. Mitsubishi F1M biplanes replaced the E8Ns from 1942 on.Skulski, pp. 25–26
Fire control and sensors When completed in 1915, Fusō had two and two rangefinders in her forward superstructure, a rangefinder on the roof of Turret No. 2, and 4.5-meter rangefinders in Turrets 3, 4, and 5. In late 1917 a fire-control director was installed on a platform on the foremast. The 4.5-meter rangefinders were replaced by instruments in 1923. During the ship's first modernization, four directors for the 12.7 mm AA guns were added, one each on each side of the fore and aft superstructures, and an eight-meter rangefinder was installed at the top of the pagoda mast. This was replaced by a rangefinder during 1938. At this same time, the two 3.5-meter rangefinders on the forward superstructure were replaced by directors for the 25 mm AA guns. Additional 25 mm directors were installed on platforms on each side of the funnel.Skulski, pp. 28–29, 82, 84
While in drydock in July 1943, Type 21 air search radar was installed on the roof of the 10-meter rangefinder at the top of the pagoda mast. In August 1944, two Type 22 surface search radar units were installed on the pagoda mast and two Type 13 early warning radar units were fitted on the funnel. Fusō was the only Japanese battleship to mount radar on her funnel.Skulski, p. 26
Construction and service
Given a classical name for Japan,Silverstone, p. 328 Fusō was laid down at the Kure Naval Arsenal on 11 March 1912 and launched on 28 March 1914. She was commissioned on 8 November 1915 and assigned to the 1st Division,Skulski and Preston use Squadron while Hackett uses BatDiv, presumably Battleship Division. of the 1st Fleet on 13 DecemberSkulski, p. 12 under the command of Captain Kōzō Satō. The ship did not take part in any combat during World War I, as there were no longer any forces of the Central Powers in Asia by the time she was completed; she patrolled off the coast of China during that time. The ship served as the flagship of the 1st Division during 1917 and 1918.Preston, p. 199 During the ship's period in reserve in 1918, five 76.2 mm anti-aircraft guns were installed. She aided survivors of the Great Kantō earthquake between 9 and 22 September 1923. Captain Mitsumasa Yonai assumed command on 1 July 1924 and was relieved on 1 November by Captain Sankichi Takahashi. In the 1920s, Fusō conducted training off the coast of China and was often placed in reserve.Skulski, pp. 12, 28
The first phase of the ship's first modernization began on 12 April 1930 at the Yokosuka Naval Arsenal; machinery was replaced, armor was reinforced, and torpedo bulges were fitted. Fusō arrived on 26 September 1932 at Kure Naval Arsenal, where her armament was upgraded and her torpedo tubes were removed. Her sea trials began on 12 May 1933, and the second phase of her modernization began less than a year later. The ship's stern was lengthened and work was completed in March 1935. Captain Jinichi KusakaSkulski, p. 13 was assigned command from November 1935 to December 1936. After sporadic use for training for the next two years, Fusō was assigned as a training ship in 1936 and 1937.Skulski, pp. 12–13, 29