''An improved version of the long-range, four-engine large bomber, "Shinzan". Developed based on large passenger aircraft from the US, the engines were replaced and the airframe improved, but problems remained and it again wasn't adopted by the military. Its features would be adopted by its successor, the Renzan. | ''An improved version of the long-range, four-engine large bomber, "Shinzan". Developed based on large passenger aircraft from the US, the engines were replaced and the airframe improved, but problems remained and it again wasn't adopted by the military. Its features would be adopted by its successor, the Renzan. |