The Hitachi Hatsukaze (初風, Hatsukaze - fresh wind), also known as the Hitachi GK4 (short Navy), Hitachi Army Type 4 110hp Air Cooled Inline (Army long), Hitachi Ha47 (Army Hatzudoki) and Ha-11 model 11 (unified), was Hitachi's fourth design in a series of
aircraft engine
An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Most aircraft engines are either piston engines or gas turbines, although a few have been rocket powered and in recent years many ...
s built in Japan prior to and during
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
. The original Hatsukaze was a license-built
Hirth HM 504
The Hirth HM 504 is a four-cylinder air-cooled inverted inline engine. The HM 504 was a popular engine for light aircraft of the 1930s-1940s, and it was used to power a number of Germany's trainer aircraft of World War II. The engine featured a ...
. Hatsukaze engines were air-cooled, four-cylinder, inverted inline engines developing around 82 kW (110 hp).
[Francillon p. 505.]
Design and development
Hatsukaze engines were produced in very large numbers, as the powerplant for the license-built
Bücker Bü 131 ''Jungmann'' variants that were the standard primary
trainers 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 ...
and
Imperial Japanese Army
The was the official ground-based armed force of the Empire of Japan from 1868 to 1945. It was controlled by the Imperial Japanese Army General Staff Office and the Ministry of the Army, both of which were nominally subordinate to the Emperor o ...
.
The naval version of the engine was designated GK4, the army version as Ha47.
The ''Hatsukaze Model 12'' was the power section linked to a
compressor
A compressor is a mechanical device that increases the pressure of a gas by reducing its volume. An air compressor is a specific type of gas compressor.
Compressors are similar to pumps: both increase the pressure on a fluid and both can transp ...
to create a primitive
jet engine
A jet engine is a type of reaction engine discharging a fast-moving jet of heated gas (usually air) that generates thrust by jet propulsion. While this broad definition can include rocket, Pump-jet, water jet, and hybrid propulsion, the term ...
called a
motorjet
A motorjet is a rudimentary type of jet engine which is sometimes referred to as ''thermojet'', a term now commonly used to describe a particular and completely unrelated pulsejet design.
Design
At the heart the motorjet is an ordinary pist ...
; the resulting
Ishikawajima Tsu-11 was intended to power
Yokosuka MXY7 Ohka
The Yokosuka MXY-7 was a purpose-built, rocket-powered aircraft, rocket-powered human-guided ''kamikaze'' attack aircraft employed by Japan against Allied ships towards the end of the Pacific War during World War II. Although extremely fast, t ...
Model 22
flying bomb
A flying bomb is a manned or unmanned aerial vehicle or aircraft carrying a large explosive warhead, a precursor to contemporary cruise missiles. In contrast to a bomber aircraft, which is intended to release bombs and then return to its base for ...
s. The standard Hatsukaze Model 11 engine was modified at a Navy arsenal by replacing the propeller drive shaft and engine front crankcase cover with a step-up gearbox. The gearbox increased engine output shaft RPM at a 1:3 ratio. At engine speed of 3,000 rpm, the compressor section was operating at 9,000 rpm. The compressed air was then ducted into a combustion chamber where a liquid fuel was sprayed and burnt. The heated compressed air then exits through the tailpipe providing static thrust of . It is likely that about 1/3 of the total thrust was contributed by adding the combustion chamber aft of the compressor.
The Tsu-11 was also selected to power the
Yokosuka MXY9 Shuka
The Yokosuka MXY9 ''Shuka'' (秋花, "Autumn flower") was a projected development of the MXY8 training glider, adding a small motorjet engine, the Tsu-11. It was intended to provide further training for pilots who were to fly the Mitsubishi J8 ...
("Autumn Fire"), a trainer intended to prepare pilots for the Mitsubishi J8M rocket-powered interceptor. Neither of these aircraft entered service, however, as their development took place too late in the war.
Variants
;GK4 Hatsukaze
:license-built Hirth HM 504 inverted inline four-cylinder aviation engine.
;GK4A Hatsukaze 11
:IJNAS (Imperial Japanese Navy Air Service) version, ; 339 built.
[Bridgeman]
;Ha47 Model 11
:(long designation Army Type 4 110hp Air Cooled Inline) IJAAS (Imperial Japanese Army Air Service) version, ; 1,037 built.
;Hatsukaze Toku Model 13
: ("Toku" translates as "special") power section for the
Ishikawajima Tsu 11 motorjet engine
Applications
*
Kyushu K9W
is the third-largest island of Japan's five main islands and the most southerly of the four largest islands ( i.e. excluding Okinawa). In the past, it has been known as , and . The historical regional name referred to Kyushu and its surroun ...
1 Type 2 Momiji ("Cypress") license built Bücker Bü 131s.
*
Kokusai Ki-86 Type 4 ("Cypress") license built Bücker Bü 131s.
Specifications (Hatsukaze GK4A)
See also
References
Notes
Bibliography
* Bridgeman, Leonard. "The Bücker Bü 131B 'Jungmann'." ''Jane's Fighting Aircraft of World War II''. London: Studio, 1946. .
* Francillon, R.J. ''Japanese Aircraft of the Pacific War''. London, Putnam, 1970. .
*
* Jackson, Paul. ''Jane's All The World's Aircraft 2003–2004''. Coulsdon, UK: Jane's Information Group, 2003.
{{Hitachi aeroengines
Air-cooled aircraft piston engines
1930s aircraft piston engines
Inverted aircraft piston engines
Motorjet engines
Hitachi