Nakajima G5N Shinzan

In 1938, with success of the Mitsubishi G4M attack bomber, the Japanese Navy issued requirement for an advanced four-engine heavy bomber which could operate more long-range and bomb load than the G4M. Nakajima and Kawanishi were selected to create two new bombers, one was the land-based airplane and the other was flying boat. Kawanishi agreed to tackle the flying boat that became H8K Emily, and Nakajima took the land-based bomber that led to the G5N Shinzan program. The G5N Shinzan was the first Japanese largest aircraft ever built. The Japanese Army also interested in this heavy bomber. The Army owned Douglas DC-4E was hand-overed to Nakajima for both the Navy G5N and Army Ki-68 programs start. Nakajima engineers took the wings, landing gears and powerplant installation from the DC-4E to complete the G5N1 prototype. The first prototype made its first flight in 1942. Performance was disappointing as the DC-4E. Totally six prototypes were completed. Four prototypes were converted to G5N-2 transport airplane. Due to the lack of experience with large aircraft development, the G5N program was cancelled in 1944.