The Gasuden Koken (also known as the ) was a Japanese long-range research aircraft of the 1930s. It was designed by the Aeronautical Research Institute of

Tokyo Imperial University The University of Tokyo (, abbreviated as in Japanese and UTokyo in English) is a public university, public research university in Bunkyō, Tokyo, Japan. Founded in 1877 as the nation's first modern university by the merger of several Edo peri ...

and built by the Tokyo Gas and Electric Industry (also known as Gasuden), to break the world record for longest flight, setting a closed circuit world record of 11,651.011 km (7,240 mi) in March 1938.

Development and design

In 1931, the Aeronautical Research Institute of the

commenced studies to design an aircraft to break the world closed-circuit distance record, gaining a grant from the Japanese

Diet Diet may refer to: Food * Diet (nutrition), the sum of the food consumed by an organism or group * Dieting, the deliberate selection of food to control body weight or nutrient intake ** Diet food, foods that aid in creating a diet for weight loss ...

or parliament to finance the project. Initial design was completed in August 1934, and the Tokyo Gas and Electric Company (also known as Gasuden) was selected to build the aircraft, despite the fact that it had only limited resources, and had previously only built small numbers of wooden light aircraft.Koken Long-range Research-plane Takenaka, K. ''Classic Airplane Museum''. 24 July 2007.
Retrieved 24 July 2009. The design produced by the Aeronautical Research Institute and Gasuden was a single-engined low-wing

cantilever A cantilever is a rigid structural element that extends horizontally and is unsupported at one end. Typically it extends from a flat vertical surface such as a wall, to which it must be firmly attached. Like other structural elements, a cantilev ...

monoplane A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple wings. A monoplane has inherently the highest efficiency and lowest drag of any wing con ...

with retractable undercarriage. It was of all-metal construction, with fabric-covered outer wings and control surfaces. While it was originally intended to be powered by a

diesel engine The diesel engine, named after the German engineer Rudolf Diesel, is an internal combustion engine in which Combustion, ignition of diesel fuel is caused by the elevated temperature of the air in the cylinder due to Mechanics, mechanical Compr ...

, this proved impracticable, and in the end a modified version of the German BMW VIII gasoline-fuelled engine, license-built by Kawasaki, was chosen. Construction was slow, and the aircraft was not completed until March 1937. It was first flown on 25 May 1937, piloted by

Major Major most commonly refers to: * Major (rank), a military rank * Academic major, an academic discipline to which an undergraduate student formally commits * People named Major, including given names, surnames, nicknames * Major and minor in musi ...

Yuzo Fujita of the

Imperial Japanese Army The Imperial Japanese Army (IJA; , ''Dai-Nippon Teikoku Rikugun'', "Army of the Greater Japanese Empire") was the principal ground force of the Empire of Japan from 1871 to 1945. It played a central role in Japan’s rapid modernization during th ...

Operational history

The first two attempts at breaking the record, on 13 November 1937 and 10 May 1938 were unsuccessful, owing to undercarriage problems and an

autopilot An autopilot is a system used to control the path of a vehicle without requiring constant manual control by a human operator. Autopilots do not replace human operators. Instead, the autopilot assists the operator's control of the vehicle, allow ...

failure respectively. The Koken-Ki took off for a third attempt from

Kisarazu, Chiba is a Cities of Japan, city located in Chiba Prefecture, Japan. , the city had an estimated population of 136,023 in 63,431 households and a population density of 980 persons per km2. The total area of the city is . Geography Kisarazu is loca ...

at 04:55 on 13 May 1938, flying a four-sided course of 402 km (249 mi). After 29 laps of the circuit, at 19:21 on 15 May, it landed at Kisarazu, having flown a distance of 11,651.011 km (7,239 mi), a new world closed-circuit distance record. This record, which remains the only aviation record ever set by Japan that was recognised by the

Fédération Aéronautique Internationale The World Air Sports Federation (; FAI) is the world governing body for air sports, and also stewards definitions regarding human spaceflight. It was founded on 14 October 1905, and is headquartered in Lausanne, Switzerland. It maintains worl ...

, the world governing body for aviation records, remained standing until August 1939, when it was broken by an Italian Savoia-Marchetti SM.82 which flew 12,936 km (8,038 mi). The Koken-ki was used for occasional test flights, last flying in 1939, and survived

World War II World War II or the Second World War (1 September 1939 – 2 September 1945) was a World war, global conflict between two coalitions: the Allies of World War II, Allies and the Axis powers. World War II by country, Nearly all of the wo ...

only to be burned following the end of the war. A full-scale replica of the Koken-ki is on display at the Misawa Aviation & Science Museum in

Misawa, Aomori is a Cities of Japan, city located in Aomori Prefecture, Japan. , the city had an estimated population of 38,198 in 19493 households, and a population density of 330 persons per km2. The total area of the city is . Misawa is the location of a l ...

Specifications

References

;Notes ;Bibliography * *

External links

航研機の紹介および各種展示-【山本峰雄サイバー・ミュージアム】Mineo Yamamoto Cyber Museum

Tag Archives: Gasuden Koken-ki / Important Dates in Aviation History / This Day in Aviation
{{Gasuden aircraft 1930s Japanese experimental aircraft Single-engined tractor aircraft Low-wing aircraft Aircraft first flown in 1937 Aircraft with fixed conventional landing gear

Development and design

Operational history

Specifications

See also

References

External links