Abstract: The invention concerns a blade profile for aircraft rotor, comprising, between a leading edge (1A) and a trailing edge (1B), a suction face (2) and a blade face (3) whereof the geometric locus of the equidistant points of the latter defines the curvature. The invention is characterised in that the value of the ratio of the maximum curvature to the maximum thickness develops linearly with the profile (1) relative thickness and ranges between 0.13 and 0.19 for a relative thickness of 7% of the chord (C) and ranges between 0.18 and 0.24 for a relative thickness of 15% of the chord (C).

Abstract: This invention relates to a section for shrouded propeller blade, of which the relative thickness is included between 9% and 15%, wherein, the curvature of said section having a maximum value at the leading edge thereof, the upper surface line comprises three successive portions, such thatin the first portion, the curvature decreases rapidly from said maximum value at the leading edge to a value close to 20 at a first point of which the reduced abscissa is close to 1%;in the second portion, the curvature decreases more slowly from said value close to 20 at said first point up to a value close to 1 at a second point, of which the reduced abscissa is close to 25%; andin the third portion, the curvature is less than 1 between said second point and said trailing edge.

Abstract: The present invention relates to a blade section for rotating wings of an aircraft comprising, between the leading edge and the trailing edge, a convex lower surface and an upper surface which is convex over the greater part of its length, but concave near the trailing edge. According to the invention, the upper surface of the section comprises a region of small extent, close to the leading edge but not contiguous thereto, in which the curvature is substantially constant. The invention is applicable to the improvement of the performances in maneuvering flight, while hovering and in advance flight of the aircraft.