Patent ID: 8789793

Claim:
An aircraft tail surface, comprising: a leading edge having a first section, extending between 0%-60% of a length of the leading edge, without an undulated shape and a second section, extending between 60%-100% of the length of the leading edge, with an undulated shape formed by a continuous series of smooth protrusions and recesses that includes a first undulation comprising a first protrusion peak, a first recess bottom, a second recess bottom, a convex surface extending continuously between the first protrusion peak and the first recesses bottom, and a concave surface extending continuously between the first protrusion peak and the second recesses bottom so that, in icing conditions, ice accretion is produced only on peaks of said protrusions and on bottoms of said recesses, thereby creating a channeled airflow and an arrangement of air vortices which impart energy to the airflow in an aerofoil boundary layer which delay airflow separation that causes a stall, thus reducing detrimental effects of the ice accretion to aerodynamic performance of the tail surface.