The Mitsubishi Ki-40 was a design for a long range twin-engined aircraft based on the Ki-39 fighter. The Ki-39 design was produced in response to a 1937 army specification for a twin-engine heavy fighter that was issued to Mitsubishi, Nakajima and Kawasaki. While working on the Ki-39 Mitsubishi also considered producing a long range version of the aircraft, which gained the designation Ki-40. Neither design progressed very far, and in mid-1937 Mitsubishi was allowed to stop work on the project. The effort wasn't wasted, for on 12 December 1937 the Army issued Mitsubishi with a specification for a new long range reconnaissance aircraft. Much of the work done on the Ki-39 and Ki-40 would be used in the development of this aircraft, the Mitsubishi Ki-46 Dinah.
How to cite this article:
Rickard, J (pending), Mitsubishi Ki-40 , http://www.historyofwar.org/articles/weapons_mitsubishi_ki-40.html