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. The Kasei (Mars) was the largest of the manufacturer’s original 14-cylinder radials, and was widely used in various models. Between 1941 and 1945, 9,323 engines of all Kasei model series were manufactured.

The model Kasei 23, which used fan cooling and water-methanol injection, suffered from early destructive vibration at certain critical rotational speeds. This problem was eventually solved by improved engine mounting shock dampers and propeller modifications. It powered various models of the Mitsubishi J2M Raiden (Thunderbolt and Allied code name Jack), a single engine fighter aircraft that also suffered many development problems. A total of 476 J2M aircraft were built, and did perform well at the end of the war in defense of Japan.

 Display Status

This object is not on display at the National Air and Space Museum. It is either on loan or in storage.
Object Details
Date Circa World War II Country of Origin Japan Type PROPULSION-Reciprocating & Rotary Manufacturer Mitsubishi Jukogyo K. K.
 Physical Description Type: Reciprocating, 14 cylinders, 2 rows, radial, water-methanol injection, fan cooling Power rating: 1,394 kW (1,870 hp) Displacement: 42.1 L (2,570 cu in.) Bore and Stroke: 150 mm (5.91 in.) x 170 mm (6.69 in.) Weight: Not available Dimensions Diameter 134 cm (52.75 in.), Length 274.32 cm (108 in.)
 Materials Aluminum, Steel, Magnesium, Rubber, Cork, Paper, Brass, Bronze, Copper, Textile, Paint, Preservative coating
 Inventory Number A19670097000 Credit Line Found in the collection Data Source National Air and Space Museum Restrictions & Rights Usage conditions apply
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