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Wright Vertical 4

The Wright Vertical 4 was an American aircraft engine built by the Wright brothers in the very early years of powered flight. It was a liquid-cooled piston engine with four inline cylinders, mounted vertically. It generated about 30–40 horsepower (22–30 kW) from a displacement of 240 cubic inches and weighed about 160–180 pounds (73–82 kg). Developed by Orville Wright in 1906, the Vertical 4 was produced by the Wright Company until 1912 and was the most numerous engine they manufactured. Around one hundred Vertical 4 engines were built, according to a Wright test foreman.

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Wright Vertical 4
Wright Vertical 4 aircraft engine on display at the Steven F. Udvar-Hazy Center. This particular engine was used on the Wright B-1 seaplane that crashed in 1912. A patch was bolted to the side of the crankcase in an attempt to repair the engine.
TypeLiquid-cooled inline-4 piston aero engine
National originUnited States
ManufacturerWright Company
Designer
Major applications
Number builtaround 10012

The Wright Vertical 4 was an American aircraft engine built by the Wright brothers in the very early years of powered flight. It was a liquid-cooled piston engine with four inline cylinders, mounted vertically (earlier Wright engines were mounted horizontally). It generated about 30–40 horsepower (22–30 kW) from a displacement of 240 cubic inches (3.9 liters) and weighed about 160–180 pounds (73–82 kg). Developed by Orville Wright in 1906, the Vertical 4 was produced by the Wright Company until 1912 and was the most numerous engine they manufactured.34 Around one hundred Vertical 4 engines were built, according to a Wright test foreman.12

The Vertical 4 powered most Wright aircraft during this period, including the Model A and Model B and variants built for the U.S. Army and Navy.

This engine was also built under license by Bariquand et Marre in France and by Neue Automobil-Gesellschaft in Germany.52


Applications


Engines on display

Wright Vertical 4 engines can be seen on display in the following museums, among others:

Specifications

Right side view of the Wright Vertical 4 on display at the National Air and Space Museum. This engine was originally a keepsake of Orville Wright's. source ↗

Data from "Wright Vertical 4, In-line 4 Engine (inventory A19620037000)". Smithsonian National Air and Space Museum. Retrieved 12 June 2018.

General characteristics

  • Type: 4-cylinder, liquid-cooled inline piston aircraft engine
  • Bore: 4.375 in (111 mm)
  • Stroke: 4 in (102 mm)
  • Displacement: 240 in3 (3.9 L)
  • Length: 40.75 in (1,035 mm)
  • Width: 18 in (457 mm)
  • Height: 27 in (686 mm)
  • Dry weight: 160–180 lb (70–80 kg)64
  • Designer: Orville Wright

Components

  • Valvetrain: overhead valve, two valves per cylinder, "automatic" intake valve (driven by suction), exhaust valve actuated by camshaft and pushrod
  • Cooling system: liquid-cooled

Performance

  • Power output: Initially 28 hp (21 kW) at 1325 rpm, later up to 42 hp (31 kW) at 1500 rpm.64
References

References

  1. Hobbs, p. 63.
  2. Lippincott, p. 89.
  3. Hobbs, p. 34.
  4. Lippincott, p. 87.
  5. Hobbs, p. 43.
  6. Hobbs, p. 62.
Bibliography

Bibliography

Hobbs, Leonard S. (1971). Smithsonian Annals of Flight, No. 5: The Wright Brothers' Engines and Their Design (PDF). Washington, D.C.: Smithsonian Institution Press.

Lippincott, Harvey H. (1987). "Propulsion Systems of the Wright Brothers". In Wolko, Howard S. (ed.). The Wright Flyer: An Engineering Perspective. Washington, D.C.: Smithsonian Institution Press. pp. 87–89. ISBN 0-87474-979-4.

McFarland, Marvin W., ed. (1953). The Papers of Wilbur and Orville Wright, Including the Chanute-Wright Letters and Other Papers of Octave Chanute. Vol. Two: 1906–1948. New York: McGraw-Hill. pp. 1215–1216.

External links