Gasuden Koken

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.