The Kawasaki Ha40, also known as the Army Type 2 1,100 hp Liquid Cooled In-line and Ha-60, was a license-built Daimler-Benz DB 601Aa 12-cylinder liquid-cooled inverted-vee aircraft engine. The

Imperial Japanese Army Air Service The Imperial Japanese Army Air Service (IJAAS) or Imperial Japanese Army Air Force (IJAAF; ja, 大日本帝國陸軍航空部隊, Dainippon Teikoku Rikugun Kōkūbutai, lit=Greater Japan Empire Army Air Corps) was the aviation force of the Im ...

(IJAAS) selected the engine to power its

Kawasaki Ki-61 The Kawasaki Ki-61 ''Hien'' (飛燕, "flying swallow") is a Japanese World War II fighter aircraft. Used by the Imperial Japanese Army Air Service, it was designated the "Army Type 3 Fighter" (三式戦闘機). Allied intelligence initially b ...

fighter.

Design and development

The Daimler-Benz DB 601Aa was a development of the earlier DB 600, with direct fuel injection replacing the carburetor. Like all DB 601s, it had a 33.9-litre displacement. The first prototype with the direct fuel injection was test run in 1935, and an order for 150 engines was placed in February 1937. A manufacturing license was granted to

Aichi is a prefecture of Japan located in the Chūbu region of Honshū. Aichi Prefecture has a population of 7,552,873 () and a geographic area of with a population density of . Aichi Prefecture borders Mie Prefecture to the west, Gifu Prefecture ...

for the production of this engine for the

Imperial Japanese Navy The Imperial Japanese Navy (IJN; Kyūjitai: Shinjitai: ' 'Navy of the Greater Japanese Empire', or ''Nippon Kaigun'', 'Japanese Navy') was the navy of the Empire of Japan from 1868 to 1945, when it was dissolved following Japan's surrender ...

as the Atsuta and to Kawasaki for production of this engine for the IJAAS as the Ha40. Under the 1944 Unified System, this engine was re-designated as the Kawasaki Ha-60. The Kawasaki Ha40 and the Aichi Atsuta were based on the engine that powered Germany's

Messerschmitt Bf 109 The Messerschmitt Bf 109 is a German World War II fighter aircraft that was, along with the Focke-Wulf Fw 190, the backbone of the Luftwaffe's fighter force. The Bf 109 first saw operational service in 1937 during the Spanish Civil War an ...

fighter.

Ha201

A new high-horsepower narrow-profile engine was required for the

Kawasaki Ki-64 The Kawasaki Ki-64 (Allied code name: Rob) was a one-off prototype of an experimental heavy, single seat, fighter. It had two unusual design features. First; it had two Kawasaki Ha-40 engines in tandem; one in the aircraft nose, the other behind ...

experimental fighter. The aircraft design called for a narrow-profile fuselage, and the solution that Kawasaki developed was the Ha-201 engine. Although similar to the Aichi Ha-70, where two Aichi Atsuta engines, mounted side-by-side behind the cockpit driving a single large propeller — an arrangement already used by the Daimler-Benz DB 606 that powered the Heinkel He 119 reconnaissance monoplane prototypes, and later inspired Japan's own Yokosuka R2Y reconnaissance aircraft from the seventh and eighth He 119 prototypes being sold to Japan in May 1940 — for the Japanese Ki-64, its own powerplant installation design called for the two Kawasaki Ha-40 engines to be separately mounted, one in the aircraft's nose, the other behind the cockpit. The engines were connected to a common gearbox that was mounted in the nose. The rear engine was connected to the nose-mounted gearbox by a long drive shaft similar to the American

Bell P-39 Airacobra The Bell P-39 Airacobra is a fighter produced by Bell Aircraft for the United States Army Air Forces during World War II. It was one of the principal American fighters in service when the United States entered combat. The P-39 was used by t ...

. The gearbox did not combine the power output of the two engines. Instead, the rear engine drove the forward controllable-pitch propeller, while the front engine independently drove the rearward fixed-pitch propeller.Francillon, p.121

Variants

;Ha40 :Up to 1,175 PS (864 kW) at sea level with 2,500 rpm, up to 1,100 PS (809 kW) at 2,400 rpm and altitude. Used in the Kawasaki Ki-61. ;Ha-60: Unified designation for the Ha40 ;Ha140:An up-rated 1,500 hp development of the Ha40 for the high-altitude Kawasaki Ki-61-II KAI interceptor aircraft. ;Ha201 :Two Ha40 coupled together with a common gearbox, driving a twin three-blade contra-rotating propeller. Used in the Kawasaki Ki-64. The combination was rated at 2,350 PS (1,728 kW) at sea level and 2,500 rpm, up to 2,200 PS (1,618 kW) at 2,400 rpm and 3,700 m altitude. ;Ha-72: Unified designation of the Ha201, coupled Ha40

Applications

;Ha40 *

;Ha201 *

Specifications (Ha40)

References

Notes

Bibliography

* Monogram Closeup 13. . * Francillon, R. J., Japanese Aircraft of the Pacific War, Putnam, London, 1970 SBN 370 00033 1 *

External links

Aviation History.com, DB 600 series page

Kurfürst - Resource on Messerschmitt Bf 109 performance.
{{Japanese Imperial Army aeroengines 1930s aircraft piston engines Inverted aircraft piston engines