Submarines of the Imperial Japanese Navy
Imperial Japanese Navy (IJN) submarines formed by far the most varied fleet of submarines of World War II, including manned torpedoes ("Kaiten"), midget submarines ("Kō-hyōteki", ), medium-range submarines, purpose-built supply submarines (many used by the Imperial Japanese Army, see Type 3), fleet submarines (many of which carried an aircraft), submarines with the highest submerged speeds of the conflict ("Sentaka" ), and submarines able to carry multiple bombers (World War II's largest submarine, the Sentoku ). They were also equipped with the most advanced torpedo of the conflict, the oxygen-fuelled Type 95 (which are sometimes confused with the famed Type 93 Long Lance torpedo).
Japanese submarine tender Karasaki
At the end of 1904, "Karasaki Maru" was sent to the Yokosuka Naval Arsenal for conversion into a submarine tender. She was officially commissioned into the Imperial Japanese Navy on 4 July 1905. On 8 March 1906, she was renamed "Karasaki", and was officially re-designated as a torpedo boat tender. In August 1912, the Imperial Japanese Navy abolished the torpedo boat tender classification, and "Karasaki" was re-designated as a second-class "kaibokan". However, the designation of torpedo boat tender was revived in April 1920. From 1924, "Karasaki" was then assigned to the submarine training school at Kure Naval District, and from 1 December 1924, was again officially designated as a submarine tender.