Misplaced Pages

#132867

25-676: Daimler-Benz granted Aichi Kokuki KK, a part of the Aichi Clock and Electric Co. (Aichi Tokei Denki KK), a license to manufacture the DB 600A through D models in November, 1936. At that time the Aichi Aircraft Company was building only the Nakajima Kotobuki 9-cylinder air-cooled radial engine at its Atsuta Engine Plant, located in south central Nagoya . It was necessary to re-tool the factory for

50-531: A firsthand account stating that one had a 1,200 hp Atsuta 12 engine, while the others three had Atsuta 32's. The first aircraft's engine was later changed to an Atsuta 32. Eighteen M6A1 Special Attack Bomber versions followed, and these had the Atsuta 32 engine as well. Lastly, two of the original M6A1 prototypes were converted into M6A1-K Nanzan land-based training aircraft. Aichi manufactured 873 Atsuta series engines during World War II. These were shared between

75-498: Is always 11, meaning the first major design and first minor version of that design. A major change to the design increments the first number and resets the second number to one. A minor change to the engine model increments the second number by one. If a very minor change is made, suffix letters are added after the model number. When the AE1A engine was accepted by the IJNAS, its coded designation

100-667: The Lawrance A-3 two-cylinder air-cooled horizontally opposed engine. At the time the Lawrence was an oddity. Most air-cooled engines at that time were rotary engines using cylinders that rotated together with the propeller , but Kimihei overheard that an engine with good cooling capability with fixed cylinders was being developed in England. He observed the English Gloster Gamecock fighter with its Bristol Jupiter engine, which

125-475: The " Ha-5 Ha-41 Ha-109 " series. Data from Gunston . Kawasaki Ha-40 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 (IJAAS) selected the engine to power its Kawasaki Ki-61 fighter. The Daimler-Benz DB 601Aa

150-615: The AE1P design was accepted, Aichi's version became the Atsuta 32 and Kawasaki's version became the Ha-40, which was to be used in IJAAS's Kawasaki Ki-61 Hien (Allied reporting name "Tony") fighter. The Atsuta 12 rated at 1200 hp was chosen to power the Yokosuka D4Y1 when it went into production. The D4Y2 was powered by the 1400 hp Atsuta 32 when it became available. The success of both airplanes

175-649: 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 fighter. A new high-horsepower narrow-profile engine was required for the Kawasaki Ki-64 experimental fighter. The aircraft design called for a narrow-profile fuselage, and the solution that Kawasaki developed

200-531: The IJAAS's Kawasaki Ki-61 , which then became known as the Kawasaki Ki-100 . Such a modification was not possible for the Aichi M6A1 Seiran as it could only use the liquid-cooled inverted-vee type engine, in order to fit into I-400-class submarine 's confined hangar, becoming the only Japanese airplane that retained the inverted-vee engine installation through to the end of the war. Postwar evaluation by

225-547: 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 gearbox did not combine

250-823: The Japanese Navy had also acquired the German He 118 V4 two-seat dive bomber aircraft, along with its production rights. This aircraft was powered by the DB 601A. The Heinkel's spectacular performance impressed the IJN Naval Staff so much that the design of the Yokosuka D4Y Suisei (Allied reporting name "Judy") carrier based dive bomber evolved from it. By 1939, eleven of the more advanced model DB 601A engines were imported. Manufacturing rights were updated for Aichi and granted to Kawasaki to build this model. The new engine received AE1P as its experimental designation. When

275-679: The Nakajima factory. After studying the Pratt & Whitney Wasp 9-cylinder radial, Nakajima tried to combine the good points found in Jupiter design with the rational design of the Wasp. Nakajima then produced a series of engine types, named "AA", "AB", "AC", and "AD", as engineering exercises. The next engine design, the "AE", was innovative, with a bore of 160 mm and a stroke of 170 mm. Prototypes were made and performance tests were done, but this engine

SECTION 10

#1733094433133

300-853: The US Air Technical Service Command 's Foreign Aircraft Evaluation Centre for the Air Force (located at Wright Field and Freeman Army Airfield ) found the Atsuta engine's standard of workmanship was not as good as that of the Army's Kawasaki Ha-40 , and far worse than Mitsubishi and Nakajima. It was the Imperial Japanese Navy's common practice to refer to its engines by name, while the Imperial Japanese Army referred to its engines by their engine (Japanese:Hatsudoki abbreviated Ha) model number. Ha numbers were assigned in sequence as

325-511: The engine design was accepted. The Japanese method of identifying model numbers of aircraft engines is unique in that the model number always has two digits and may be followed by one or more letters. The first digit represents the major version of the engine and the second number represents the minor version of that model engine. The model number follows the name (IJNAS engines) or the Ha number (IJAAF engines). The first model number assigned to an engine

350-482: The production of the new Daimler-Benz engine. Two DB 600 engines were imported that year and three the next, all to be used as production patterns. It was the Imperial Japanese Navy's common practice to use a coded designation while an engine was in experimental or pre-production status. This engine was coded "AE1A", which decodes as: A=Aichi Tokei Denki KK, E=Liquid-cooled, 1=Aichi's first liquid-cooled engine model, and A=first version of that engine model. By early 1938

375-557: The summer. Then flight tests were started using a Nakajima A2N carrier plane. Nakajima had designed the first Japanese originally designed air-cooled 9-cylinder engine, the 450 PS "Kotobuki". In December 1931, this engine was approved and adopted by the Navy as the Ha-1 Ko for the Type 97 carrier fighter . The engine was named, in connection with the Jupiter engine, "Kotobuki". The "Kotobuki" engine

400-576: The twenty-two M6A1/M6A1-K and all D4Y1/2 aircraft. Peak production of the Atsuta 32 engine was in May, 1944, when 107 engines were produced. A serious problem with the Aichi and Kawasaki version of the Daimler-Benz engine was that of holding a close tolerance fit between the crankshaft and its bearings on this fairly long engine. The result was that the engine proved to be prone to crankshaft failure. Additionally, there

425-624: 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 for the production of this engine for the Imperial Japanese Navy as the Atsuta and to Kawasaki for production of this engine for

450-543: Was an advanced design for the era with an automatic adjustment device for tappet clearance, spiral piping for even intake distribution, and a four-valve intake and exhaust system. He acquired a manufacturing license for the Jupiter in 1925. In 1927, after inviting two production engineer instructors from the Bristol company, the Jupiter Type 6 of 420 PS and Type 7 of 450 PS with a supercharger were put into production at

475-650: Was an aero-engine developed by Nakajima . It was a radial piston developed under licence from the Bristol Jupiter . In 1917, Chikuhei Nakajima set up the "Airplane Institute" at Ojima Town in Gunma Prefecture . In 1918 they built their first airplane; the "Nakajima Type 1" with a U.S.A. made engine. In 1920 the company sent Kimihei Nakajima to France to study European advances, and in 1922 started their own engine factory in Tokyo. This led to production of engines based on

500-550: Was attributed to the slender lines of the high powered liquid-cooled engine. A new top-secret aircraft that was to be transported and launched from a large submarine was ordered by the IJN in the spring of 1942 as the 17-Shi Special Attack Bomber. That aircraft became the Aichi M6A Serian ( Shisei-Seiran ), along with its M6A1-K Ninzan ( Shisei-Seiran Kai ) land-based trainer version. Four preproduction M6A aircraft were completed,

525-644: Was dropped and it was named after the Atsuta factory where the engine was manufactured. The first production engine was the Atsuta 12 rated at 1200 hp. The model number 12 indicates this was the first model with one minor change. Under the Japanese unified designation system introduced around 1942-3 the Ha is separated from the number by a hyphen which is absent under the IJAAS system. Data from The First Naval Technical Arsenal. Related development Comparable engines Related lists Nakajima Kotobuki The Nakajima Ha1 Kotobuki (寿, "Longevity")

SECTION 20

#1733094433133

550-402: Was improved and developed into the " Hikari (light)" engine with the bore and stroke expanded to the limit of the cylinder (160 × 180 mm for a displacement of 32.6 L), with the power was increased to 720 PS. The "Hikari" was used in Type 95 carrier fighters and Type 96 Carrier Attack Plane . In search of more power the basic design was extended into a 14-cylinder 2-row engine,

575-405: Was not adopted due to its very complex engineering. Nakajima continued testing different cylinder designs. In 1929, the "AH" design, with bore and stroke of 146 × 160 mm and a total displacement of 24.1 L, was completed. This was to be the final version of this basic engine design. In June 1930 the first prototype of was completed and it passed the durability test for the type approval in

600-540: Was often great difficulty obtaining engine components which, along with repeated air attacks on the Atsuta engine plant, eventually brought engine production to a standstill. Maintenance difficulties with the Atsuta and Ha-40 engines eventually led to the installation of the more reliable Mitsubishi Kinsei 62 radial engine for the Yokosuka D4Y3 Model 33 , and the Mitsubishi Ha-112 radial air-cooled engine for

625-662: 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

#132867