Japanese battleship Satsuma Background . The " Satsuma " class was ordered in late 1904 under the 1904 War Naval Supplementary Program during the Russo - Japanese War . Unlike the previous pre - dreadnought battleship s , they were the first battleships ordered from Japanese shipyards , although " Satsuma " used a lot of imported components . They were originally designed with a dozen guns , but had to be redesigned because of a shortage of guns in Japan and to reduce costs . Design and description . The ship had an overall length of , a beam of , and a normal draft of . She displaced at normal load . The crew ranged from 800 to 940 officers and enlisted men . " Satsuma " was powered by a pair of vertical triple - expansion steam engines , each driving one propeller , using steam generated by 20 Miyabara water - tube boilers using a mixture of coal and fuel oil . The engines were rated at a total of and designed to reach a top speed of . During the ship ' s sea trials she reached from . " Satsuma " carried enough coal and oil to give her a range of at a speed of . The ship was completed with four 45 - caliber 12 - inch 41st Year Type guns in two gun turrets , one each fore and aft of the superstructure . They fired armor - piercing ( AP ) shells to a maximum range of . The intermediate armament consisted of six twin - gun turrets equipped with 45 - caliber Type 41 10 - inch guns , three turrets on each side of the superstructure . Her heavy intermediate armament is why the ship is considered to be a semi - dreadnought . " Satsuma " was equipped with a dozen 40 - caliber 4 . 7 - inch 41st Year Type quick - firing ( QF ) guns , mounted in casemates in the sides of the hull . The ship was also equipped with four 40 - caliber 12 - pounder 12 - cwt QF guns and four 28 - caliber 12 - pounder QF guns . In addition , she was fitted with five submerged torpedo tube s , two on each broadside and one in the stern . The waterline main belt of the " Satsuma " - class vessels consisted of Krupp cemented armor that had a maximum thickness of amidships . It tapered to a thickness of inches at the ends of the ship . A strake of armor protected the casemates . The barbettes for the main guns were thick . The armor of " Satsuma " s main gun turrets had a maximum thickness of nine inches . The deck armor was thick and the conning tower was protected by six inches of armor . Construction and career . " Satsuma " , named for Satsuma Province , was laid down at Yokosuka Naval Arsenal on 15 May 1905 . She was launched on 15 November 1906 with Emperor Meiji , the Navy Minister , and other high officials on hand for the ceremony , and completed on 25 March 1910 . At the time of her launching , " Satsuma " had the largest displacement of any battleship in the world . On 5 August 1911 , the ship suffered an explosion in one of her 12 - inch guns when it failed to fire during gunnery practice . After some time passed , the breech was opened and ignited the propellant ; the resulting fire killed 16 crewmen and several officers . She was lightly damaged by a typhoon on 22 September 1912 . " Satsuma " was assigned to the 1st Battleship Squadron when World War I began in August 1914 . She served as Rear Admiral Tatsuo Matsumura ' s flagship in the Second South Seas Squadron as it seized the German possessions of the Caroline and the Palau Islands in October 1914 . " Satsuma " rejoined the 1st Battleship Squadron in 1915 , was refitted at Sasebo Naval Arsenal in 1916 and served with the 1st Squadron for the rest of the war . Sometime during the war , she was fitted with two 12 - pounders on high - angle mounts to serve as anti - aircraft gun s . The ship was disarmed at Yokosuka Naval Arsenal in 1922 to comply with the provisions of the Washington Naval Treaty , stricken from the Navy List on 20 September 1923 and converted into a target ship . " Satsuma " was sunk by the battleships and in Tokyo Bay on 7 September 1924 .