The Homare (Honor) was Japan’s most-used engine in the latter years of World War II. Fan cooling, fuel injection, turbo-supercharging and water-methanol injection differed in various versions. All models suffered from unreliability, service difficulty (particularly when first entering service), and vibration.

The artifact powered the Yokusuka P1Y1 Ginga (Milky Way) (Allied Code Name FRANCES) twin- engine aircraft, which is in the museum’s collection, for low-altitude torpedo and dive-bombing attacks. Several of these aircraft carried out Kamikaze suicide attacks against American warships. This particular NK9C (Ha45-12) engine also model powered the Aichi B7A2 Ryusei (Shooting Star) single engine torpedo bomber (Allied Code Name GRACE), the largest and heaviest Japanese carrier-based aircraft to fly in World War II, and is similarly in the museum’s collection.

 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 1945 Country of Origin Japan Type PROPULSION-Reciprocating & Rotary Physical Description Type: Reciprocating, 18 cylinders, 2-rows, radial, air cooled Power rating: 1,361 kW (1,825 hp) Displacement: 35.9 L (2,195 cu in.) Bore and Stroke: 130 mm (5.1 in.) x 150 mm (5.9 in.) Weight: Unknown Dimensions Length 157.5 cm (62 in.), Width 152.4 cm (60 in.), Height 189.2 cm (74.5 in.) (Approximate)
 Materials Aluminium
Paint
Steel
Plastic
Adhesive
Magnesium Alloy
Rubber
Natural Fabric
 Inventory Number A19600340005 Credit Line Transferred from the U.S. Air Force Data Source National Air and Space Museum Restrictions & Rights Usage conditions apply
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