Fokker S.I

The Fokker S.I was a Dutch primary trainer, first flown in 1919 and the first of a family of trainers from the Fokker company.

Fokker S.I
Fokker S.I TW-4 V.44 front.jpg
Role Primary trainer
Manufacturer Fokker
Designer Reinhold Platz
First flight 1919
Primary users USSR
United States Army Air Service
Number built 3 (and one prototype)


The S.I was designed by Reinhold 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[citation needed] and only three production aircraft were built.

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).


  Soviet Union
  United States

Specifications (TW-4)Edit

Data from Wesselink[1]

General characteristics

  • Crew: 2
  • Length: 8.91 m (29 ft 3 in)
  • Wingspan: 12.71 m (41 ft 8 in)
  • Gross weight: 893 kg (1,969 lb)
  • Propellers: 2-bladed


  • Maximum speed: 138 km/h (86 mph, 75 kn)

See alsoEdit

Related lists


  1. ^ Wesselink 1982


  • 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