was the lead ship of her class of two dreadnought battleships built for the Imperial Japanese Navy (IJN) during the 1910s. Although completed in 1917, she played no role in World War I. Ise supported Japanese forces in the early 1920s during the Siberian Intervention in the Russian Civil War. In 1923, she assisted survivors of the Great Kantō earthquake. The ship was partially modernised in two stages in 1928–1929 and 1931–1932, during which her forward superstructure was rebuilt in the pagoda mast style. Ise was reconstructed in 1934–1937, with improvements to her armour and her propulsion machinery. Afterwards she played a minor role in the Second Sino-Japanese War.
Despite the expensive reconstruction, the ship was considered obsolete by the eve of the Pacific War, and did not see significant action in the early years of the war. Following the loss of most of the IJN's large aircraft carriers during the Battle of Midway in mid-1942, she was rebuilt with a flight deck replacing the rear pair of gun turrets to give her the ability to operate an air group of floatplanes; lack of aircraft and qualified pilots meant that Ise never actually operated aircraft in combat. She participated in the Battle off Cape Engaño in late 1944, where she was one of the ships that decoyed the American carrier fleet supporting the invasion of Leyte away from the landing beaches. Afterwards the ship was transferred to Southeast Asia. In early 1945 Ise participated in Operation Kita, where she transported petrol and other strategic materials to Japan. The ship was then reduced to reserve until American airstrikes in July sank her. After the war Ise was scrapped in 1946–1947.
Design and description
The Ise class was designed as an improved version of the preceding . The ships had a length of overall, a beam of and a draught of at deep load.Lengerer March 2007, p. 9 They displaced at standard load and at deep load, roughly more than the earlier ships. Their crew consisted of 1,360 officers and ratings.
During the ships' modernisation in the 1930s, their forward superstructure was enlarged with multiple platforms added to their tripod masts to create a pagoda mast. Both ships were also given torpedo bulges to improve their underwater protection and to compensate for the weight of the extra armour. These changes increased their overall length to ,Chesneau, p. 171 their beam to and their draught to . Their displacement increased by over to at deep load.Lengerer 2009, pp. 50–51 The crew now numbered 1,376 officers and enlisted men.
Propulsion The Ise-class ships had two sets of direct-drive steam turbines, each of which drove two propeller shafts, using steam provided by 24 Kampon Ro Gō water-tube boilers. The turbines were designed to produce a total of and give the ships a speed of . Ise reached from during her sea trials.Lengerer 2011, pp. 21–22 Each of the boilers consumed a mixture of coal and oil, and the ships carried enough of both to give them a range of at a speed of .Jentschura, Jung & Mickel, p. 26
During their 1930s modernisation, the boilers on each ship were replaced by eight new Kampon oil-fired boilers. The turbines were replaced by four geared Kampon turbines with a designed output of intended to increase their speed to . On her trials, Ise reached a top speed of from . The fuel storage of the ships was increased, which gave them a range of at a speed of , despite the additional weight.
Armament The twelve Type 41 guns of the Ise class were mounted in three pairs of twin-gun, superfiring turrets that were numbered one through six from front to rear. The first pair was forward of the main superstructure, the second pair was amidships, and the last ones were aft of the rear superstructure.Lengerer 2011, pp. 24–26, 30 The ships' secondary armament consisted of twenty Type 3 guns in single mounts. Eighteen of these were mounted in casemates in the forecastle and superstructure and the remaining pair were mounted on the deck above them and protected by gun shields.Lengerer 2011, pp. 33–34 Anti-aircraft defence was provided by four 3rd Year Type 8-centimetre (3 in) anti-aircraft (AA) guns in single mounts. The ships were also fitted with six submerged torpedo tubes, three on each broadside.Gardiner & Gray, p. 230
In 1931–1933 the AA guns were replaced with eight Type 89 dual-purpose guns, placed beside the forward superstructure in four twin-gun mounts.Lengerer March 2007, p. 12 Two twin-gun mounts for licence-built Vickers two-pounder () light AA guns were also added, while the pair of 14 cm guns on the upper deck were removed.Hackett, Kingsepp & Ahlberg
During the mid-1930s reconstruction, the torpedo tubes were removed and the Vickers two-pounders were replaced by 20 licence-built Hotchkiss Type 96 light AA guns in 10 twin-gun mounts. This was the standard Japanese light AA gun during World War II, but it suffered from serious design shortcomings that heavily reduced its effectiveness. 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 During the reconstruction the forward pair of 14-centimetre guns in the forecastle were removed and the maximum elevation of the remaining guns was increased to +30 degrees.
Protection The Ise-class ships' waterline protective belt had a maximum thickness of of Vickers cemented armour amidships; below it was a strake of armour. The upper armoured deck consisted of two layers of high-tensile steel totaling thick and the lower armoured deck also consisted of two layers of high-tensile steel, but only thick in total.Lengerer 2006, pp. 28–30; Lengerer 2011, p. 36 The turrets were protected with an armour thickness of on the face and 76 mm on the roof.Lengerer March 2007, p. 16 The casemate armour was thick and that of the barbettes was 299 mm thick rather than the originally planned 305 mm.Lengerer 2006, pp. 28–30
Fire control and sensors While the details of the ship's fire-control instruments are not fully available, Ise was fitted with a gunnery director after completion. In the late 1920s the fire-control systems were upgraded and additional platforms were added to the foremast to accommodate them. A pair of directors for the 12.7 cm AA guns were added in the early 1930s, one on each side of the forward superstructure. The fire-control systems were again upgraded in the mid-1930s and directors were added for the 2.5 cm AA guns.Lengerer 2011, pp. 28, 30–31, 41 The ship had a rangefinder installed at the top of the pagoda mast at that time. Type 21 air-search radars were installed aboard the ship in mid-1942.
Aircraft Ise was briefly fitted with an aircraft flying-off platform for a Mitsubishi 1MF3 fighter on Turret No. 2 in 1927. It was replaced by a platform on Turret No. 5 for a Yokosuka E1Y reconnaissance floatplane in 1928–1929. A catapult and a collapsible crane were fitted on the stern during the mid-1930s modernisation, 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.
Construction and career
Ise, named after Ise Province, one of the traditional provinces of Japan, was laid down at the Kawasaki Heavy Industries shipyard in Kobe on 5 May 1915 and launched on 12 November 1916. Captain Akizawa Yoshima assumed command on 1 December and the ship was completed on 15 December 1917, too late for service in World War I.Silverstone, p. 331 Ise was assigned to the 1st Division of the 1st Fleet in 1917–1918. Captain Kuwashima Shozo relieved Akizawa on 1 December 1918 and he was relieved in his turn by Captain Furukawa Hiroshi on 20 November 1919. On 29 August 1920, the ship began the first of numerous patrols off the Siberian coast and in northern waters in support of Japan's Siberian Intervention against the Bolshevik Red Army. Captain Yokoo Hisashi replaced Furukawa on 20 November and he was replaced by Captain Nagasawa Naotaro in his turn on 1 December 1921.
On 12 April 1922, while at Yokohama, Ise hosted a delegation which included the Prince of Wales (the future King Edward VIII), and his second cousin, the future Lord Mountbatten of Burma. Captain Kanna Norikazu relieved Nagasawa on 1 December. The ship aided survivors of the Great Kantō earthquake in September 1923. From the early 1920s through the late 1930s, Ise mostly cruised off the coast of China. Little detailed information is available about her activities during the 1920s, although she helped sink the obsolete destroyer during gunnery training on 10 August 1926. The ship was overhauled in 1928–1929, during which her forward superstructure was enlarged and her aviation facilities improved.
Between 20 November 1931 and 10 February 1932, Ise had her anti-aircraft armament entirely replaced, her forward superstructure was further enlarged so that it became a pagoda mast, and her stern was modified in preparation for a catapult and crane at Kure Naval Arsenal. These were installed between 14 May and 6 June 1933. On 15 November, she became a training ship. Ises crew participated in the state funeral of Marshal-Admiral The Marquis Tōgō Heihachirō, victor of the 1905 Battle of Tsushima, on 15 June 1934.
Beginning on 1 August 1935, Ise was drydocked at Kure Naval Arsenal and underwent an extensive reconstruction and modernisation that lasted until 23 March 1937. On 9 April 1938, the ship began the first of her patrols off the southern Chinese coast during the Second Sino-Japanese War that lasted until early 1941. She was transferred to the 2nd Division of the 1st Fleet on 15 November 1940 and became its flagship on 15 November 1941. Captain Takeda Isamu assumed command of Ise on 25 September 1941.
Start of the Pacific War To provide distant support for the 1st Air Fleet attacking Pearl Harbor on 8 December,Japan Standard Time is 19 hours ahead of Hawaiian Standard Time, so in Japan, the attack on Pearl Harbor happened on 8 December. the division, reinforced by the battleships and and the light carrier , sortied from Hashirajima to the Bonin Islands and returned six days later. Ise had a minor refit at the Kure Naval Arsenal in 19–25 February 1942. Together with the rest of the division, she pursued, but did not catch, the American carrier force that had launched the Doolittle Raid on 18 April. On 11 May Ise had an accident which flooded her No. 2 engine room. While under repair, the ship was fitted with one of the first experimental Type 21 early-warning radar sets in the IJN, but it was removed shortly afterwards.
Ise and the rest of the 2nd Battleship Division set sail on 28 May with the Aleutian Support Group at the same time most of the Imperial Fleet began an attack on Midway Island (Operation MI).Rohwer, pp. 168–169Parshall & Tully, p. 454 Commanded by Vice-Admiral Shirō Takasu, the division was composed of Japan's four oldest battleships, including Ise, accompanied by two light cruisers, 12 destroyers, and two oilers. Official records do not show the division as part of the larger Midway operation, known as Operation AL; they were to accompany the fleet under Admiral Isoroku Yamamoto, but were only to provide support to the Aleutian task force if needed.Parshall & Tully, p. 46
Conversion to a hybrid carrier