Onishi OSG3

The Onishi OSG3 is a 1970s Japanese single-seat motor glider, designed and built by Yuichi Onishi (大西勇一,Onishi Yuichi). This was his second motor-glider design; the first being a high-wing monoplane, powered by a Subaru car engine, with which he made a 120 km flight between Chigasaki and Oshima Island in July 1970.

Design and development
The OSG3 is unusual in being powered by six model aircraft engines, which are arranged along a transverse strut-braced boom near the front of the fuselage. Together, the six engines produce 7.5 kW for take-off, and 5.6 kW for cruising flight. There are six throttle levers and also six cut-out switches for the engines. The aircraft has a cantilevered monoplane wing, in a shoulder-wing position on the fuselage. The empennage has a T-tail configuration.

Design of the OSG3 began in January 1976, with construction commencing in July of that year. By January 1977, the aircraft had been completed and taxiing trial conducted.