The Type A2 submarine was a single class of submarine in the Imperial Japanese Navy during World War II, consisting of one boat, I-12, equipped with an aircraft. The design was similar to the earlier Type A1 submarine, except for the A2's having weaker engines. The boat thus had a lower surfaced speed but a longer range. USS Ardent (AM-340) and USS Rockford (PF-48) sank a Japanese submarine on 13 November 1944. Postwar research reveals that it was most likely I-12.