Type AM submarine

The AM (A Modified) type submarine was a large seaplane-carrying submarine of the Imperial Japanese Navy, with a hangar space for 2 aircraft. These giant submarines were originally of the A2 type, meant to act as command boats for groups of submarines, but their design was revised after construction started so that they could carry a second aircraft. Seven units were ordered, but only two (I-13 and I-14) were completed, while construction of two more was abandoned in March 1945, with construction of the remaining three submarines never started. The seaplanes were to be the Aichi M6A1, bomber carrying 800 kg bombs.

The range and speed of these submarines was remarkable (21,000 nmi at 16 knots), but their underwater performance was compromised, making them easy targets. I-13 was sunk on 16 July 1945 by the destroyer escort USS Lawrence C. Taylor and aircraft action from escort carrier USS Anzio about 550 nmi east of Yokosuka. I-14 surrendered at sea at the end of the war, and was scuttled off Oahu in 1946. In 2009 researchers at the Hawaii Undersea Research Laboratory found I-14 at a depth of about 2600 ft.