Aichi Ha-70
The Aichi Ha-70 was a compound engine composed of two 1,700 hp 12-cylinder liquid-cooled inverted V-12 Aichi Atsuta aircraft engines mounted to a common gearbox. The only aircraft powered by the Ha-70 was the Yokosuka R2Y, an Imperial Japanese Navy Air Service (IJNAS) prototype reconnaissance aircraft that was designed and built near the end of World War II. Design and development In common with Daimler-Benz, Aichi Kokuki KK joined two Aichi Atsuta engines to drive a single propeller through a combining gearbox in very similar fashion to the Daimler Benz DB 606 (two Daimler-Benz DB 601 engines coupled to a gearbox), The Yokosuka R2Y prototype reconnaissance aircraft required a new engine of and after studying the Daimler-Benz DB 606A-2 engine that powered the Heinkel He 119 single-engine reconnaissance bomber, Aichi determined that the required horsepower could be attained by coupling two Atsuta engines with a common gearbox. To obtain the required power the Atsuta would require up-rating by at least horsepower; Aichi continued to improve the Atsuta 32, eventually extracting the required The two inverted Vee Atsuta engines were mounted side-by-side, each rotated outboard from the centre-line so that the inner banks were upright, with sufficient room between them for