A stall strip is a small component fixed to the

leading edge The leading edge of an airfoil surface such as a wing is its foremost edge and is therefore the part which first meets the oncoming air.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 305. Aviation Supplies & Academics, ...

of the

wing A wing is a type of fin that produces lift while moving through air or some other fluid. Accordingly, wings have streamlined cross-sections that are subject to aerodynamic forces and act as airfoils. A wing's aerodynamic efficiency is expres ...

of an

airplane An airplane or aeroplane (informally plane) is a fixed-wing aircraft that is propelled forward by thrust from a jet engine, propeller, or rocket engine. Airplanes come in a variety of sizes, shapes, and wing configurations. The broad spe ...

to modify its aerodynamic characteristics.Crane, Dale: ''Dictionary of Aeronautical Terms'', third edition, page 487. Aviation Supplies & Academics, 1997. These stall strips may be necessary for the airplane to comply with

type certification A type certificate signifies the airworthiness of a particular category of aircraft, according to its manufacturing design (''type design''). It confirms that the aircraft of a new type intended for serial production, is in compliance with applica ...

requirements. A stall strip typically consists of a small piece of material, usually aluminium, triangular in cross section and often 6-12 inches (15–30 cm) in length. It is

rivet A rivet is a permanent mechanical fastener. Before being installed, a rivet consists of a smooth cylindrical shaft with a head on one end. The end opposite to the head is called the ''tail''. On installation, the rivet is placed in a punched ...

ed or bonded to the wing’s leading edge. Some airplanes have one stall strip on each wing. Some airplanes have only one stall strip on one wing.

Operation

A stall strip initiates

flow separation In fluid dynamics, flow separation or boundary layer separation is the detachment of a boundary layer from a surface into a wake. A boundary layer exists whenever there is relative movement between a fluid and a solid surface with viscous fo ...

on a region of the upper surface of the wing during flight at high

angle of attack In fluid dynamics, angle of attack (AOA, α, or \alpha) is the angle between a reference line on a body (often the chord line of an airfoil) and the vector representing the relative motion between the body and the fluid through which it is m ...

. This is typically to avoid a tendency to

spin Spin or spinning most often refers to: * Spinning (textiles), the creation of yarn or thread by twisting fibers together, traditionally by hand spinning * Spin, the rotation of an object around a central axis * Spin (propaganda), an intentionally b ...

following a stall, or to improve the controllability of the airplane as it approaches the stall. A stall strip may be intended to alter the wing’s stall characteristics and ensure that the

wing root The wing root is the part of the wing on a fixed-wing aircraft or winged-spaceship that is closest to the fuselage,Peppler, I.L.: ''From The Ground Up'', page 9. Aviation Publishers Co. Limited, Ottawa Ontario, Twenty Seventh Revised Edition, 1996 ...

stalls before the

wing tips A wing tip (or wingtip) is the part of the wing that is most distant from the fuselage of a fixed-wing aircraft. Because the wing tip shape influences the size and drag of the wingtip vortices, tip design has produced a diversity of sha ...

. In some cases, such as the American Aviation AA-1 Yankee, both wings are designed to incorporate stall strips. In the case of the AA-1 the left and right wings were identical, interchangeable and built on a single wing jig, thus the more traditional use of washout in the wing design was not possible. Stall strips are usually factory-installed but, on rarer occasions, may be an after-market modification.

References

External links

Stall Origins and Performance, Whittsflying website - accessed 09 March 2008
{{Aircraft components Aircraft wing components

Operation

See also

References

External links