[Caustic]

History of Japanese Submarines in World War 2.

Japan had what was easily the most diverse submarine fleet of any nation in the Second World War. These included manned torpedoes, midget submarines, medium-range submarines, purpose-built supply submarines (many for use by the Army), long-range fleet submarines (many of which carried an aircraft), submarines with high submerged speed, and submarines that could carry multiple bombers.

Because of the vastness of the Pacific, Japan built many boats of extreme range and size, many of which were capable of cruises exceeding 20,000 miles and lasting more than 100 days. In fact, Japan built what were by far the largest submarines in the world, indeed, the only submarines over 5,000 tons submerged displacement, or submarines over 400 feet in length until the advent of nuclear power. These same boats were credited with a range of 37,500 miles at 14 knots, a figure never matched by any other diesel-electric submarine. These large boats could each carry three floatplane bombers, the only submarines in history so capable. Japan built 41 submarines that could carry one or more aircraft, while the vast submarine fleets of the United States, Britain, and Germany included not one submarine so capable.