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.