Clark Y

From Wikipedia, the free encyclopedia

Clark Y is the name of a particular aerofoil profile, widely used in general purpose aircraft designs, and much studied in aerodynamics over the years. The profile was designed in 1922 by Virginius E. Clark. The airfoil has a thickness of 11.7 percent and is flat on the lower surface from 30 percent of chord back. The flat bottom simplifies angle measurements on propellors, and makes for easy construction of wings on a flat surface.

For many applications the Clark Y has never been bettered; it gives good overall performance in respect of its lift-to-drag ratio, and has gentle and relatively benign stall characteristics. The Lockheed Vega is one example of the Clark Y in practice.

The Clark YH airfoil was the same but with a reflexed (turned up) trailing edge producing a more positive pitching moment for improved lateral stability. The Hawker Hurricane used this profile. Мany Soviet aircraft of the 1930s and 1940s including all of the World War II Yakovlev fighters and MiG-3 used the Clark YH airfoil (Shavrov 1994).

Clark YH wingroot of a Yak-18T
Enlarge
Clark YH wingroot of a Yak-18T


[edit] References

  • Шавров В.Б. (1994) История конструкций самолетов в СССР 1938-1950 гг. (3 изд.). Машиностроение (Shavrov V.B. (1994) Istoriia konstruktskii samoletov v SSSR, 1938-1950 gg. (3rd ed.). Mashinostroenie. ISBN 5-217-00477-0) (History of aircraft design in USSR: 1938-1950)