An aircraft leading edge is extended by an aerodynamic surface providing an aerodynamic flow and where air discharges are arranged preventing separation of the aerodynamic flow. The air discharges are arranged in at least two rows essentially parallel to the leading edge and in an offset manner for at least two consecutive rows. At least one block is inserted between two walls that form the aerodynamic surface. The block includes, on the one hand, an outside surface extending the aerodynamic surface, a first inclined surface contacting the first wall forming the aerodynamic surface, and a second inclined surface contacting the second wall that forms the aerodynamic surface, and, on the other hand, projecting and/or hollow shapes that are made at the inclined surfaces and that are arranged in an alternating fashion from one surface to the next, allowing air to pass on both sides of the aerodynamic surface.