The MF-85 was a composite four seat aircraft, planned to be offered with 134 to 183 kW (180 to 245 hp) engines, priced at DM245,000 to DM325,000 (excluding avionics), with optional fixed or retractable undercarriage.

The prototype (V001 D-EEHE) first flew with a 212 hp (158 kW) Porsche PFM 3200N, driving a 3-bladed Mühlbauer MTV.9 constant speed propeller, on 8 August 1988, piloted by Horst Ruschmeyer.

Despite promising flight test results, the unavailability of Porsche engines led to the development of the Textron Lycoming powered R 90.

Powered by a Lycoming IO-540-C4D5 driving a Mühlbauer MTV.14-B constant speed propeller, the production R 90-230RG was built from 1988 to the mid-1990s in Germany.

The engine is de-rated to 172 kW (231 hp) to reduce noise, but still enables the R 90 to reach a maximum cruising speed of 324 km/h (175 kn; 201 mph).