The St Croix Sopwith Triplane is an American

homebuilt aircraft Homebuilt aircraft, also known as amateur-built aircraft or kit planes, are constructed by persons for whom this is not a professional activity. These aircraft may be constructed from "scratch", from plans, or from assembly kits.Armstrong, Kenn ...

that was designed and produced by

St Croix Aircraft St Croix Aircraft, was an American manufacturer of wooden propellers for homebuilt and ultralight aircraft and a supplier of aircraft plans and kits. The company headquarters was located in Corning, Iowa.Purdy, Don: ''AeroCrafter - Homebuilt A ...

Corning, Iowa Corning is a city in Quincy Township, Adams County, Iowa, United States. The population was 1,564 at the 2020 census. It is the county seat of Adams County. Corning is located just north of the intersection of U.S. Route 34 and Iowa Highway 148 ...

. When it was available the aircraft was supplied as a kit or in the form of plans for amateur construction. The aircraft is a full-size replica of the 1916

Sopwith Triplane The Sopwith Triplane was a British single seat fighter aircraft designed and manufactured by the Sopwith Aviation Company during the First World War. It has the distinction of being the first military triplane to see operational service. T ...

fighter aircraft.Purdy, Don: ''AeroCrafter - Homebuilt Aircraft Sourcebook, Fifth Edition'', page 249. BAI Communications, 15 July 1998.

Design and development

The aircraft features a cantilever strut-braced

triplane A triplane is a fixed-wing aircraft equipped with three vertically stacked wing planes. Tailplanes and canard foreplanes are not normally included in this count, although they occasionally are. Design principles The triplane arrangement may ...

layout, a single-seat, with an optional two-seats-in-

tandem Tandem, or in tandem, is an arrangement in which a team of machines, animals or people are lined up one behind another, all facing in the same direction. The original use of the term in English was in ''tandem harness'', which is used for two ...

open cockpit, fixed

conventional landing gear Conventional landing gear, or tailwheel-type landing gear, is an aircraft undercarriage consisting of two main wheels forward of the center of gravity and a small wheel or skid to support the tail.Crane, Dale: ''Dictionary of Aeronautical Ter ...

and a single engine in

tractor configuration In aviation, the term tractor configuration refers to an aircraft constructed in the standard configuration with its engine mounted with the propeller in front of it so that the aircraft is "pulled" through the air. Oppositely, the pusher co ...

. The St Croix Sopwith Triplane differs from the original 1916 design in that it employs a welded steel tube

fuselage The fuselage (; from the French ''fuselé'' "spindle-shaped") is an aircraft's main body section. It holds crew, passengers, or cargo. In single-engine aircraft, it will usually contain an engine as well, although in some amphibious aircraft t ...

, modern engine installation and other minor details. The Triplane is all covered in doped

aircraft fabric Aircraft fabric covering is a term used for both the material used and the process of covering aircraft open structures. It is also used for reinforcing closed plywood structures. The de Havilland Mosquito is an example of this technique, as are ...

. Its span wing uses strut and cable-bracing and has a wing area of . The cabin width is . The acceptable power range is and the standard engine used is the

Lycoming O-435 The Lycoming O-435 is an American six-cylinder, horizontally opposed fixed-wing aircraft and helicopter engine made by Lycoming Engines. The engine is a six-cylinder version of the four-cylinder Lycoming O-290. Design and development The po ...

powerplant. The St Croix Sopwith Triplane has a typical empty weight of and a gross weight of , giving a useful load of . With full fuel of the payload for the pilot, passengers and baggage is . The standard day, sea level, no wind, take off with a engine is and the landing roll is . The manufacturer estimated the construction time from the supplied kit as 4000 hours.

Operational history

By 1998 the company reported that 25 kits had been sold and 15 aircraft were completed and flying.

Specifications (St Croix Sopwith Triplane)

References

External links

* {{St Croix aircraft

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