| Koken | |
|---|---|
| |
| Role | Long range research aircraft |
| National origin | Japan |
| Manufacturer | Gasuden |
| First flight | 25 May 1937 |
| Number built | 1 |
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 11,651.011 km (7,240 mi) in March 1938.