EFF / Entwicklungsgemeinschaft für Flugzeugbau Prometheus II / Prometheus PV
The Prometheus is a production of EFF / Entwicklungsgemeinschaft für Flugzeugbau / Association for the development project and airplane building. It is is a high performance side-by-side glider with two Microturbo 90 kp thrust engines. A self-launching glider, its engines can be stopped and reset running at will.
One was built, registered in 1978 as HB-YBI, and the name Prometheus PV.
With a wingspan of 19.4 m, it weighs 707 kg unladen and 900 at full load. Its radius of action powered flight exceeds 500 Km
In 1980, the manufacturer reported a radio navigation facility and a transponder allowing it to integrate seamlessly resctriction in controlled airspace and major airport.
The Prometheus II is linked to an engineer in Switzerland, Ulrich La Roche , who sought to reproduce with WINGGRID, some aerodynamic effect on birds. This work began in the first wind tunnel at Emmen between 1993 and 1994. In 1996, an encounter with Prof . Dr. - Ing. Hans -Reinhard Meyer- Piening would offer the opportunity to validate the concept of a real WINGGRID demonstrator.
In 1997, the Prometheus was chosen for this experiment. To this end, the size was reduced to 12 m. They hoped a glide ratio of 15 to 17, but experience showed that it was 25. The Prometheus II is a high performance glider with a fineness approaching 40, but with a high wing loading.