Fokker S.I was a Dutch primary trainer, first flown in 1919 and the first of a family of trainers from the Fokker company.
The S.I was designed by
Rheinhold Platz as a primary trainer with a cantilever parasol wing with two side-by side seats for instructor and pupil in a wide cockpit. It first flew in early 1919 at Schwerin. Although the prototype performed well, the unusual cantilever parasol wing was not liked and only three production aircraft were built. citation needed
Two production aircraft were powered by 60 kW (80 hp)
Le Rhône engines and were exported to the USSR and one other aircraft was built for the United States Army Air Service for evaluation at McCook Field. The USAAS aircraft was powered by a 67 kW (90 hp) Curtiss OX-5 engine and was designated the TW-4 (Trainer Water-cooled).
Data from Wesselink 1
Length: 8.91 m (29 ft 3 in)
Wingspan: 12.71 m (41 ft 8 in)
Gross weight: 893 kg (1,969 lb)
Maximum speed: 138 km/h (86 mph; 75 kn)
Wesselink, Theo; Postma, Thijs (1982). De Nederlandse vliegtuigen. Haarlem: Romem. ISBN 90 228 3792 0.
The Illustrated Encyclopedia of Aircraft (Part Work 1982-1985), 1985, Orbis Publishing, Page 1899