Mitsubishi was the first and largest series producer of Japanese engines during World War II, with a 1937 Pratt & Whitney arrangement possibly contributing to this success. However, Mitsubishi did encounter difficulty later in the war when its designs were more independent. Development of this engine began in 1941, but only a small number were known to have been built before the war ended. The engine type incorporated fuel injection and fan cooling. And while there is no turbo-supercharger installed on this particular artifact, it was designed for it.
It powered two prototype Japanese twin-engine aircraft, the Tachikawa Ki-70 Army Experimental Command Reconnaissance Plane (Allied Code Name Clara) and Tachikawa Ki-74 Army Experimental Long Range Bomber (Allied Code Name Patsy). Neither of these aircraft became operational, and the engines, which were not fully developed, proved unreliable during flight tests.