01/31/2008. Remarks by Johan Visschedijk: "In 1968 Max Dätwyler announced preliminary details for a new two-seat aerobatic basic trainer. A team under the leadership of Hans Farner and the Swedish designer Björn Andreasson designed the aircraft and by 1974 a prototype was being constructed. The pictured prototype was flown for the first time on August 12, 1983, with Max Dätwyler at the controls.
A second prototype (HB-HOJ, c/n 002) and three production aircraft (HB-HNA to HB-HNC, c/n 003 to 005) were built."