2022. ;SF-25A Motor Falke :First production batch with a Hirth F10A2a engine, 56 built. ;SF-25B Falke :Improved variant with lower wing position and a 45hp Stark Stamo engine, 372 built. ;SF-25C Falke :Same as a SF-25B but with an alternator and electric starter. Sub-variants include: ::;Falke 1700: ::::49 kW (65 hp)
Limbach 1700 EA 1 IA, driving propeller at 3,450 rpm; ::;Falke 2000: ::::60 kW (80 hp)
Limbach 2000 EA, driving propeller at 3,450 rpm (about 512 Limbach powered Falkes built by 1998); ::;Rotax Falke: ::::(a) 60 kW (80 hp)
Rotax 912 A running at 5,800 rpm and geared down to 2,500 rpm propeller speed;
tricycle gear an option (about 130 Rotax powered Falkes built by 1998), or ::::(b) 75 kW (100 hp)
Rotax 912S at 5,800 rpm and geared down to 2,500 rpm propeller speed, or ::::(c) 85 kW (115 hp)
Rotax 914F3 at 5,800 rpm and geared down to 2,500 rpm propeller speed with 5 minute time limit; 75 kW (100 hp) continuous. ::;Falke 100PS: ::::Glider tug. ::;SF-25CS Falke ::::A SF-25C with a feathering propeller; feathering was an option with the Falke 1700, 2000, and Rotax Falke. ;SF-25D Falke :SF-25B converted with a Limbach 1700A engine. ;SF-25E Super Falke :A SF-25CS with extended wing, a narrow-chord vertical tail. air brakes and a raised bubble canopy, first flown in 1974. ;SF-25K K-Falke :A SF-25C with folding wings and large canopy. ;
Slinsgby T61 Falke/Slingsby Venture :Licence built variant of the SF-25B, 76 built ==Operators==