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.

Development

The S.I was designed by Reinhold Platz as a primary trainer with a

cantilever A cantilever is a rigid structural element that extends horizontally and is supported at only one end. Typically it extends from a flat vertical surface such as a wall, to which it must be firmly attached. Like other structural elements, a cant ...

parasol wing A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple planes. A monoplane has inherently the highest efficiency and lowest drag of any wing confi ...

with two side-by side seats for instructor and pupil in a wide cockpit. It first flew in early 1919 at

Schwerin Schwerin (; Mecklenburgian Low German: ''Swerin''; Latin: ''Suerina'', ''Suerinum'') is the capital and second-largest city of the northeastern German state of Mecklenburg-Vorpommern as well as of the region of Mecklenburg, after Rostock. It ...

. Although the prototype performed well, the unusual cantilever parasol wing was not liked and only three production aircraft were built. Two production aircraft were powered by

Le Rhône Le Rhône was the name given to a series of popular rotary aircraft engines produced in France by Société des Moteurs Le Rhône and the successor company of Gnome et Rhône. They powered a number of military aircraft types of the First Worl ...

engines and were exported to the

USSR The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, it was nominally a federal union of fifteen nationa ...

and one other aircraft was built for the

United States Army Air Service The United States Army Air Service (USAAS)Craven and Cate Vol. 1, p. 9 (also known as the ''"Air Service"'', ''"U.S. Air Service"'' and before its legislative establishment in 1920, the ''"Air Service, United States Army"'') was the aerial war ...

for evaluation at McCook Field. The USAAS aircraft was powered by a

Curtiss OX-5 The Curtiss OX-5 was an early V-8 American liquid-cooled aircraft engine built by Curtiss. It was the first American-designed aircraft engine to enter mass production, although it was considered obsolete when it did so in 1917.Smith, 1981, page ...

engine and was designated the TW-4 (Trainer Water-cooled).

Operators

; *

Soviet Air Force The Soviet Air Forces ( rus, Военно-воздушные силы, r=Voyenno-vozdushnyye sily, VVS; literally "Military Air Forces") were one of the air forces of the Soviet Union. The other was the Soviet Air Defence Forces. The Air Forces ...

; *

as the TW-4.

Specifications (TW-4)

Notes

References

* * * The Illustrated Encyclopedia of Aircraft (Part Work 1982-1985), 1985, Orbis Publishing, Page 1899 {{USAAS trainer aircraft 1910s Dutch military trainer aircraft S.I Aircraft first flown in 1919 High-wing aircraft Single-engined tractor aircraft

Development

Operators

Specifications (TW-4)

See also

Notes

References