Mitsubishi Shinten

The Mitsubishi Shinten, whose name means Quaking Sky, was a two-row, 14-cylinder, air-cooled radial aircraft engine built by the Mitsubishi Aircraft Company for the Imperial Japanese Army Air Service and the Imperial Japanese Navy Air Service in the early 1930s. Mitsubishi knew it internally as the A6 or A7 while it was an experimental project, the Navy called it the Shinten or MK1, and the Army designated it Ha6. It was a development of the early Kinsei: lengthening the stroke from 150 millimetres to 160 millimetres on the model 11, and to 170 millimetres on the model 21, raised the displacement from the Kinsei's 32.3 litres to 36.1 litres and take-off power from 1,070 to 1,200 horsepower. The Army meant it for the Mitsubishi Ki-21 bomber, but a competing engine, the Nakajima Ha5, was chosen instead and Mitsubishi was ordered to build that engine under licence, so only 113 Shinten engines were made. Enlarging its bore then produced the Mitsubishi Kasei.