The Type A2 submarine was a single class of submarine in the Imperial Japanese Navy

Imperial Japanese Navy

The Imperial Japanese Navy was the navy of the Empire of Japan from 1869 until 1947, when it was dissolved following Japan's constitutional renunciation of the use of force as a means of settling international disputes...

 during World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

, consisting of one boat, I-12

Japanese submarine I-12

The submarine I-12 was a Japanese A2 type submarine. She was built at the Kawasaki's shipyard in Kobe.-Wartime service:The I-12 sailed from the Inland Sea on 4 October 1944 to disrupt American shipping between the west coast and the Hawaiian Islands....

, 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.

Like the Type A1, this submarine was designed to act as a headquarters boat coordinating the operations of submarine squadrons. However, unlike the Type A1, the Type A2 submarine was ineffective in its role and in its only patrol, she sank a freighter and machine gunned the survivors.
and sank a Japanese submarine on 13 November 1944. Postwar research reveals that it was most likely I-12.