Submarines of the Imperial Japanese Navy
Imperial Japanese Navy submarines originated with the purchase of five Holland type submarines from the United States in 1904. Japanese submarine forces progressively built up strength and expertise, becoming by the beginning of World War II one of the world's most varied and powerful submarine fleets.
Type A submarine
The was a class of submarine in the Imperial Japanese Navy (IJN), which served during the Second World War. The "Type-A" submarines were built to take a role of the command ships for submarine squadrons. For this reason they had equipment for a headquarters, better radio facilities and a floatplane.