was a super-dreadnought battleship built for the Imperial Japanese Navy (IJN). Completed in 1920 as the lead ship of her class, she carried supplies for the survivors of the Great Kantō earthquake in 1923. The ship was modernized in 1934–1936 with improvements to her armor and machinery and a rebuilt superstructure in the pagoda mast style. Nagato briefly participated in the Second Sino-Japanese War in 1937 and was the flagship of Admiral Isoroku Yamamoto during the attack on Pearl Harbor. She covered the withdrawal of the attacking ships and did not participate in the attack itself.
Other than participating in the Battle of Midway in June 1942, where she did not see combat, the ship spent most of the first two years of the Pacific War training in home waters. She was transferred to Truk in mid-1943, but did not see any combat until the Battle of the Philippine Sea in mid-1944 when she was attacked by American aircraft. Nagato did not fire her main armament against enemy vessels until the Battle of Leyte Gulf in October. She was lightly damaged during the battle and returned to Japan the following month. The IJN was running out of fuel by this time and decided not to fully repair her. Nagato was converted into a floating anti-aircraft platform and assigned to coastal defense duties. She was attacked in July 1945 as part of the American campaign to destroy the IJN's last remaining capital ships, but was only slightly damaged and went on to be the only Japanese battleship to have survived World War II. In mid-1946, the ship was a target for nuclear weapon tests during Operation Crossroads. She survived the first test with little damage, but was sunk by the second.
Description
Nagato had a length of between perpendiculars and overall. She had a beam of and a draft of . The ship displaced at standard load and at full load. Her crew consisted of 1,333 officers and enlisted men as built and 1,368 in 1935. The crew totaled around 1,734 men in 1944.
thumb|left|Nagato and her crew in 1937 on the recently installed pagoda mast
In 1930, Nagatos bow was remodeled to reduce the amount of spray produced when steaming into a head sea. This increased her overall length by to . During her 1934–1936 reconstruction, the ship's stern was lengthened by to improve her speed and her forward superstructure was rebuilt into a pagoda mast. She was given torpedo bulges to improve her underwater protection and to compensate for the weight of the additional armor and equipment. These changes increased her overall length to , her beam to and her draft to . Her displacement increased over to at deep load. The ship's metacentric height at deep load was . In November 1944, the tops of Nagatos mainmast and funnel were removed to improve the effective arcs of fire for her anti-aircraft guns. In addition her turbines were replaced by lighter, more modern, units. Additional fuel oil was stored in the bottoms of the newly added torpedo bulges, which increased her capacity to and thus her range to at 16 knots. which increased the gun's maximum range from .
The ship's secondary armament of twenty 50-caliber 14-centimeter guns was mounted in casemates on the upper sides of the hull and in the superstructure. The manually operated guns had a maximum range of and fired at a rate of six to 10 rounds per minute. Anti-aircraft defense was provided by four 40-caliber 3rd Year Type three-inch These guns had a maximum elevation of +80 degrees which gave them a ceiling of . They had a maximum rate of fire of 200 rounds per minute.
thumb|upright|left|Photograph shows the rear turret, between ca. 1920 and ca. 1925
When the ship was reconstructed in 1934–1936, the remaining torpedo tubes and the two forward 14 cm (-inch) guns were removed from the hull. The remaining 14 cm guns had their elevation increased to +35 degrees which increased their range to . An unknown number of license-built Hotchkiss M1929 machine gun in twin mounts were added. The maximum range of these guns was , but the effective range against aircraft was . 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.
The unsatisfactory two-pounders were replaced in 1939 by twenty license-built Type 96 Hotchkiss Type 96 light AA guns in a mixture of twin-gun and single mounts. These 25 mm 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. and her 14 cm guns were removed as she was by then a floating anti-aircraft battery. The turrets were protected with an armor thickness of 305 mm on the face, on the sides, and on the roof.
The new 41 cm turrets installed during Nagatos reconstruction were more heavily armored than the original ones. Face armor was increased to , the sides to , and the roof to . The armor over the machinery and magazines was increased by 38 mm on the upper deck and on the upper armored deck. In early 1941, as a preparation for war,
thumb|upright=0.7|Binoculars from the Nagato on display at the [[National World War II Museum]]
Fire control and sensors
When completed in 1920, the ship was fitted with a rangefinder in the forward superstructure; and anti-aircraft rangefinders were added in May 1921 and 1923, respectively. The rangefinders in the second and third turrets were replaced by 10-meter units in 1932–1933.
Nagato was initially fitted with a Type 13 fire-control system derived from Vickers equipment received during World War I, but this was replaced by an improved Type 14 system around 1925. It controlled the main and secondary guns; no provision was made for anti-aircraft fire until the Type 31 fire-control director was introduced in 1932. A modified Type 14 fire-control system was tested aboard the ship in 1935 and later approved for service as the Type 34. A new anti-aircraft director called the Type 94 that was used to control the 127 mm AA guns was introduced in 1937, although when Nagato received hers is unknown. The Type 96 AA guns were controlled by a Type 95 director that was also introduced in 1937.
While in drydock in May 1943, a Type 21 air search radar was installed on the roof of the 10-meter rangefinder at the top of the pagoda mast. On 27 June 1944, two Type 22 surface search radars were installed on the pagoda mast and two Type 13 early warning radars were fitted on her mainmast. aircraft flying-off platform on Turret No. 2 in August 1925. Yokosuka Ro-go Ko-gata and Heinkel HD 25 floatplanes were tested from it before it was removed early the following year. in mid-1933, a collapsible crane was installed in a portside sponson, and the ship was equipped to operate two or three floatplanes, although no hangar was provided. The ship now operated Nakajima E4N2 biplanes until they were replaced by Nakajima E8N2 biplanes in 1938. A more powerful catapult was installed in November 1938 to handle heavier aircraft, such as the one Kawanishi E7K that was added in 1939–1940. Mitsubishi F1M biplanes replaced the E8Ns on 11 February 1943.
Construction and career
Nagato, named for Nagato Province, was ordered on 12 May 1916 and laid down at the Kure Naval Arsenal on 28 August 1917 as the lead ship of her class. She was launched on 9 November 1919 by Admiral Katō Tomosaburō, completed on 15 November 1920 and commissioned 10 days later with Captain Nobutaro Iida in command. Nagato was assigned to the 1st Battleship Division and became the flagship of Rear Admiral Sōjirō Tochinai. On 13 February 1921, the ship was inspected by the Crown Prince, Hirohito. Captain Kanari Kabayama relieved Iida on 1 December 1921. The ship hosted Marshal Joseph Joffre on 18 February 1922 and Edward, Prince of Wales, and his aide-de-camp Lieutenant Louis Mountbatten on 12 April during the prince's visit to Japan. and became a gunnery training ship. In August 1925, aircraft handling and take-off tests were conducted aboard Nagato. She was reassigned as the flagship of the Combined Fleet on 1 December, flying the flag of Admiral Keisuke Okada. Captain Kiyoshi Hasegawa assumed command of the ship on 1 December 1926.
Nagato was again placed in reserve on 1 December 1931 and her anti-aircraft armament was upgraded the following year. In August 1933 the ship participated in fleet maneuvers north of the Marshall Islands and she began her first modernization on 1 April 1934. This was completed on 31 January 1936 and Nagato was assigned to the 1st Battleship Division of the 1st Fleet. During the attempted coup d'état on 26 February by disgruntled Army officers, the ship was deployed in Tokyo Bay and some of her sailors were landed in support of the government. In August, she transported 1,749 men of the 43rd Infantry Regiment of the 11th Infantry Division from Shikoku to Shanghai during the Second Sino-Japanese War. Nagato became a training ship on 1 December until she again became the flagship of the Combined Fleet on 15 December 1938. The ship participated in an Imperial Fleet Review on 11 October 1940. She was refitted in early 1941 in preparation for war. she sortied for the Bonin Islands, along with Mutsu, the battleships , , , of Battleship Division 2, and the light carrier as distant cover for the withdrawal of the fleet attacking Pearl Harbor, and returned six days later. Yamamoto transferred his flag to the new battleship on 12 February 1942. Nagato was briefly refitted 15 March – 9 April at Kure Naval Arsenal. Following the loss of all four carriers of the 1st Air Fleet on 4 June, Yamamoto attempted to lure the American forces west to within range of the Japanese air groups at Wake Island, and into a night engagement with his surface forces, but the American forces withdrew and Nagato saw no action. After rendezvousing with the remnants of the 1st Air Fleet on 6 June, survivors from the aircraft carrier were transferred to Nagato. On 14 July, the ship was transferred to Battleship Division 2 and she became the flagship of the 1st Fleet. Yano was promoted to rear admiral on 1 November and he was replaced by Captain Yonejiro Hisamune nine days later. Nagato remained in Japanese waters training until August 1943. On 2 August Captain Mikio Hayakawa assumed command of the ship.
Battle of Leyte Gulf
thumb|left|Center Force sorties from Brunei Bay, Borneo: six heavy cruisers head to sea, followed by Yamato, and Nagato
Kobe was promoted to rear admiral on 15 October. Three days later, Nagato sailed for Brunei Bay, Borneo, to join the main Japanese fleet in preparation for "Operation Sho-1", the counterattack planned against the American landings at Leyte. The Japanese plan called for Ozawa's carrier forces to lure the American carrier fleets north of Leyte so that Vice Admiral Takeo Kurita's 1st Diversion Force (also known as the Center Force) could enter Leyte Gulf and destroy American forces landing on the island. Nagato, together with the rest of Kurita's force, departed Brunei for the Philippines on 22 October.
In the Battle of the Sibuyan Sea on 24 October, Nagato was attacked by multiple waves of American dive bombers and fighters. At 14:16 she was hit by two bombs dropped by planes from the fleet carrier and the light carrier . The first bomb disabled five of her casemate guns, jammed one of her Type 89 gun mounts, and damaged the air intake to No. 1 boiler room, immobilizing one propeller shaft for 24 minutes until the boiler was put back online.
thumb|right|Drawing of Nagato as she appeared in 1944
On the morning of 25 October, the 1st Diversion Force passed through the San Bernardino Strait and headed for Leyte Gulf to attack the American forces supporting the invasion. In the Battle off Samar, Nagato engaged the escort carriers and destroyers of Task Group 77.4.3, codenamed "Taffy 3". At 06:01 she opened fire on three escort carriers, the first time she had ever fired her guns at an enemy ship, but missed. At 06:54 the destroyer fired a spread of torpedoes at the fast battleship ; the torpedoes missed Haruna and headed for Yamato and Nagato which were on a parallel course. The two battleships were forced 10 miles (16 km) away from the engagement before the torpedoes ran out of fuel. Turning back, Nagato engaged the American escort carriers and their screening ships, claiming to have damaged one cruiser