 Being very similar in layout and performance, the main difference between the Kawasaki Ki-32 and its Mitsubishi Ki-30 rival was in the choice of an engine.The Mitsubishi design used the Nakajima Ha-5 14-cylinder air-cooled radial engine, whereas Kawasaki opted for their own Kawasaki Ha-9-II inline V12 engine.Problems were encountered with the Kawasaki design, particularly with engine cooling, and the Mitsubishi Ki-30 received the production order.