|Role||High speed research aircraft|
|Manufacturer||Kawasaki Kokuki Kogyo K.K. (川崎航空工機業株式会社 - Kawasaki Aircraft Industries)|
|Design group||Aeronautical Research Institute of the University of Tokyo|
|First flight||26 December 1942|
|Number built||1 completed + 1x mock-up and the partially complete 2nd prototype|
The Kawasaki Ki-78, originally given the designation KEN III (Kensan III - research III), was a high speed research aircraft, also intended to attempt breaking the World Absolute speed record.
Design and development
The Kawasaki Ki-78 was a high-speed research aircraft developed to investigate laminar profile wings with high wing loadings. Early in 1938 a high-speed research program was started at the Aeronautical Research Institute of the University of Tokyo for a small single-seat aircraft.
The Ki-78, designed at the Aeronautical Research Institute and built at Kawasaki Kokuki Kogyo K.K. to investigate flying behaviour at very high speed, featured a streamlined minimum cross-section fuselage fitted with a licence-built Daimler-Benz DB 601A engine. For short duration power boost methanol/water injection was used, and cooling was improved by a 45 kW (60 hp) turbine driven cooling fan for the radiators.
All-metal construction was used in combination with a small thin wing with a laminar flow profile and a sharp leading edge.
By the outbreak of the war, the whole project was taken over by the Imperial Japanese Army who gave it the military type designation Ki-78. Kawasaki received the order to build two prototypes of the Ki-78, construction of which was started in September 1941. The first was completed more than a year later and was flown for the first time on 26 December 1942. A feasibility study to improve the KI-78 flight performance showed that extensive airframe modifications were needed and consequently the project was officially terminated after the 32nd flight on 11 January 1944; the second Ki-78 was never completed.
Specifications (KEN III / Ki-78)
Data from Japanese Aircraft of the Pacific War
- Crew: 1
- Length: 8.1 m (26 ft 7 in)
- Wingspan: 8 m (26 ft 3 in)
- Height: 3.07 m (10 ft 1 in)
- Wing area: 11 m2 (120 sq ft)
- Empty weight: 1,930 kg (4,255 lb)
- Gross weight: 2,300 kg (5,071 lb)
- Powerplant: 1 × Daimler-Benz DB 601A V-12 inverted liquid-cooled piston engine rated at 1,160 kW (1,550 hp) with Water/Methanol injection for short durations
- Maximum speed: 700 km/h (435 mph; 378 kn) at 3,500 m (11,500 ft)
- Range: 600 km (373 mi; 324 nmi)
- Service ceiling: 8,000 m (26,247 ft)
- Wing loading: 209 kg/m2 (43 lb/sq ft)
- Power/mass: 0.373 kW/kg (0.2273 hp/lb)
- Aircraft of comparable role, configuration and era
- Air Pictorial: 489. December 1986. Missing or empty