|Role||Long range research aircraft|
|First flight||25 May 1937|
The Gasuden Koken (also known as the Kōken-ki (航研機?)) was a Japanese long-range research aircraft of the 1930s. It was 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 km (7,240 mi) in March 1938.
Development and design
In 1931, the Aeronautical Research Institute of the Tokyo Imperial University commenced studies to design an aircraft to break the world closed-circuit distance record, gaining a grant from the Japanese Diet 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. The design produced by the Aeronautical Research Institute and Gasuden was a single-engined low-wing cantilever monoplane 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, this proved impracticable, and in the end a modified version of the German BMW-VIII gasoline-fuelled engine, license-built by Kawasaki was chosen.
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 failure respectively. The Koken-Ki took off for a third attempt from Kisarazu, Chiba 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 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).
Data from Japanese Aircraft, 1910-1941
- Crew: three
- Length: 15.06 m (49 ft 5 in)
- Wingspan: 27.93 m (91 ft 7¾ in)
- Height: 3.60 m (11 ft 9¾ in)
- Wing area: 87.3 m² (939.7 sq ft)
- Empty weight: 4,225 kg (9,314 lb)
- Loaded weight: 9,216 kg  (20,317 lb)
- Powerplant: 1 × Kawasaki built BMW VIII water-cooled V12 engine, 715 hp (533 kW)
- Maximum speed: 250 km/h (135 knots, 155 mph) at sea level
- Cruise speed: 211 km/h (114 knots, 131 kmg) at 2,000 m (6,600 ft)
- Range: 11,651.011 km  (6,295.29 nmi, 7,239.58 mi)
- Service ceiling: 3,410 m (11,200 ft)
Media related to Gasuden Koken at Wikimedia Commons
- Aircraft of comparable role, configuration and era
- Mikesh and Abe 1990, p. 90.
- Koken Long-range Research-plane Takenaka, K. Classic Airplane Museum. 24 July 2007. Retrieved 24 July 2009.
- Nakamura, The Japan Times 5 July 2008, p. ?.
- Mikesh and Abe 1990, p. 91.
- Record flight
- Record distance
- Mikesh, Robert C. and Shorzoe Abe. Japanese Aircraft 1910-1941. London: Putnam Aeronautical Books, 1990. ISBN 0-85177-840-2.
- Nakamura, Akemi. Only world-record-setting Japanese plane remembered Japan Times Online, 5 July 2008. Retrieved 24 July 2009.
|Wikimedia Commons has media related to Gasuden Koken.|