After overcoming some initial reliability problems, the Homare (Honour) became the most important 18-cylinder Japanese engine toward the end of World War II. It powered aircraft with Allied Code Names George, Sam, Rita, and Frank. A very compact design, it had a very high specific output; and incorporated for the first time in a Japanese engine, a steel crankcase, dynamic balancers, a dual magneto with a remote distributor (on the nose), and a nose sump pump. Its supercharger drive followed the Wright Aeronautical design, with a planetary reduction gear in series with the high gear for obtaining a lower compression ratio. It was equipped with water-methanol injection.

 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 Nakajima Hikoki K. K.
 Physical Description Type: Reciprocating, 18 cylinders, 2 rows, radial, air-cooled, supercharged Power rating: 1,491 kW (2,000 hp) Displacement: 35.9 L (2,195 cu in) Bore and Stroke: 130 mm (5.1 in.) x 150 mm (5.9 in.) Weight: 800-900 kg (1800-2000 lb) Dimensions Overall: 46 7/16 in., 830lb. (118cm, 376.5kg)
Other: 46 7/16 x 52 x 84 x 55in. (118 x 132.1 x 213.4 x 139.7cm)
Storage: 213.4 × 139.1 × 142.2cm (84 × 54 3/4 × 56 in.)
 Materials Aluminum
Steel
Paint
Leather
Rubber
Paper
Adhesive
Cadmium Plating
Magnesium Alloy
 Inventory Number A19731565000 Credit Line Transferred from the U.S. Navy, Naval Supply Center, Cheatham Annex, Williamsburg, Virginia Data Source National Air and Space Museum Restrictions & Rights Usage conditions apply
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