On display at Gifu-Kakamigahara Air and Space Museum. Japan's National Aerospace Laboratory converted a C-1 for STOL tests and to reduce the noise footprint. Four newly-built FJR710/600S turbofans were mounted on top and ahead of the wings to generate lift using the Coandă effect by upper surface blowing (USB) through vortex generators onto the flaps. The sole Asuka or 'flying bird' was retired in March 1989 after 97 flights and 167 flight hours, achieving 509m for takeoff and 449m for landing.

This Quiet STOL research aircraft was powered by four FRJ710 turbofans and was intended to utilise the Coandă effect to generate lift by having the engine exhaust flow over the curved surface of the top of the wing. The type was also used to develop fly-by-wire systems and composite material construction. This is the only example built and is currently on display at the Kakamigahara Aviation Museum. The small Japanese 航空宇宙技術研究所 titles stand for National Aerospace Laboratory.

Based on the successful Kawasaki C-1 transport, this was a one-off Quiet STOL research aircraft, developed by the National Aerospace Laboratory. Powered by four FRJ710 turbofan engines and making use of the Coandă effect. It was built to research STOL using upper surface blowing, aircraft noise reduction, fly-by-wire systems and composite materials construction and is now displayed at the Kakamigahara Aerospace Museum outside Gifu Air Base. The small Japanese 航空宇宙技術研究所 titles stand for National Aerospace Laboratory.