The Ki-5 was initially produced by Kawasaki Kōkūki Kōgyō K.K. in response to Japanese army specifications for a high-performance fighter to replace the existing Type 92.[1] It was the first all-metal, cantilevermonoplanefighter aircraft to be built in Japan. It was designed around the Kawasaki Ha-9, a Japanese development of the BMW IXaircraft engine,[1] itself a development from the BMW VII A 7.3 liquid-cooled engine, with a nominal rating of 634 kW (850 hp). It also had the innovation of using an inverted gull wing design, to improve downward visibility for the pilot and to be able to use a simple, short undercarriage.[1]
However, the Ki-5 design quickly proved unsatisfactory in flight testing.[1]Test pilots complained of stability and handling problems, and the engine was never able to produce enough power for the Ki-5 to attain its design speed parameter of 380 km/h (240 mph).
The project was cancelled on 9 September 1934,[2] after a total of four units were produced. However, the design effort on the Ki-4 later paid off dividends with the designs for the future Ki-28, Ki-60 and Ki-61.