Stall strips

A stall strip is a fixed device employed on the leading edge of fixed-wing aircraft to modify the aerodynamic characteristics of the airfoil. Stall strips are used to initiate flow separation at chosen locations on the wing during high-angle of attack flight, so as to improve the controllability of the aircraft when it enters stall. They are typically employed in pairs, symmetrically on both wings. On aircraft where wing airflow is affected by asymmetrical propeller wash, a strip may be used on a single wing to reduce risk of entering a spin.