The Kayaba Ku-4 was a research aircraft built in Japan in 1940 to investigate the possibilities of tailless aircraft designs. It followed designer Hidemasa Kimura's successful Ku-2 and Ku-3 designs for the Imperial Japanese Army. While these previous aircraft had been gliders, however, the Ku-4 was to be a powered by a pusher engine. It had a low, swept wing, and like the Ku-2, fins at the wingtips.

Ku-4
Role	Research aircraft Type of aircraft
National origin	Japan
Manufacturer	Kayaba Industry
Designer	Hidemasa Kimura
Status	Cancelled project

Work on the prototype was well advanced by April 1941, but the following month, Kimura's relationship with the Army soured following the crash of the Ku-2. The Ku-4 was cancelled, and Kimura eventually received only ¥17,000 of the ¥200,000 that had been promised for the development of his tailless designs.

Specifications (as designed)

General characteristics

• Crew: One pilot
• Length: 3.42 m (11 ft 3 in)
• Wingspan: 9.80 m (32 ft 2 in)
• Wing area: 9.0 m² (97 sq ft)
• Powerplant: 1 × piston engine , 90 kW (120 hp)

Performance

• Maximum speed: 180 km/h (110 mph, 96 kn)
• Range: 300 km (190 mi, 170 nmi)

References

Wikimedia Commons has media related to Kayaba Ku-4.

• Wooldridge, E.T. "Japanese flying wings". History of the Flying Wing. Retrieved 29 April 2007.
• 日本飞翼的短暂研究