The Japanese submarine I-5 was the first aircraft-carrying submarine in the Imperial Japanese Navy and operated during World War II. The sole member of the Junsen 1 Mod. (巡潜一型改) class, the submarine was launched on 19 June 1931 at Kobe by Kawasaki. A single Yokosuka E6Y floatplane was carried. A catapult was fitted in 1938 but the capability to operate the aircraft was removed two years later and the boat was reconfigured as an attack submarine. By that time, I-5 had already seen wartime service.