The Aichi D1A or Navy Type 94/96 Carrier Bomber (Allied reporting name "Susie") was a Japanese carrier-based dive bomber of the 1930s. A single-engine, two-seat biplane based on the Heinkel He 50, the D1A was produced by Aichi for the Imperial Japanese Navy, remaining in service as a trainer at the time of the attack on Pearl Harbor. The D1A was produced in two variants, the D1A1 (Navy Type 94 Carrier Bomber), and the D1A2 (Navy Type 96 Carrier Bomber, sometimes referred to as the D2A.)