Submarines of the Imperial Japanese Navy
The ("I-15"-class) submarines (, , , , , , , , , , , , , , , , , , , ) were the most numerous type of submarines of the Imperial Japanese Navy during World War II. In total 20 were made, starting with "I-15", the class ship. These were fast, very long ranged, and carried a single Yokosuka E14Y seaplane, located in a hangar in front of the conning tower, launched by a catapult.
Japanese Type 6 submarine
The "Kaigun Holland" #6 was launched at Kobe on 28 September 1905 and was completed six months later at Kure as the first submarine built in Japan. It sank during a training dive in Hiroshima Bay on 15 April 1910. Although the water was only 58 feet deep, there were no provisions for the crew to escape while submerged. The commanding officer, Lieutenant Tsutomu Sakuma, patiently wrote a description of his sailor's efforts to bring the boat back to the surface as their oxygen supply ran out. All of the sailors were later found dead at their duty stations when this submarine was raised the following day. The sailors were regarded as heroes for their calm performance of their duties until death, and the submarine was preserved as a memorial in Kure until the end of World War II.