The 1938 W.F.23 motor glider/sailplane was design by Max Weber and Georg Müller, powered by a 25 hp AVA tractor engine, and featured a free-wheel hub.
The WF.23 featured a retractable main undercarriage with spring strut. Landing on a skid was possible.
The sole wood and canvas example was built by Willi Farner Flugzeugbau Grenchen as the Farner W.F.23P
Wingspan: 17.50 m
Wing area: 21.5 sq.m
Empty weight: 340 kg
Max weight: 433 kg
Wing loading: 20 kg/sq.m
Max speed: 140 km/h
ROC: 1 m/sec
Seats: 1
All Aero 