A propeller blade having a blade body including a blade base, a blade tip, a pressure side surface, and, a suction side surface. Each of the pressure side surface and the suction side surface extend between the blade base to the blade tip. An end plate is provided on the blade body. The end plate is exposed to an airflow and positioned at the blade base. The end plate projects outwardly of at least a portion of one of the pressure side surface and the suction side surface.

A propeller blade includes a first material and a second material. The first material includes fibers. The second material is different from the first material. The fibers are interspersed through the second material and the fibers are oriented in a same direction within the second material. The propeller blade is anisotropic and includes sections of the fibers.

A propeller blade includes a first material and a second material. The first material includes fibers. The second material is different from the first material. The fibers are interspersed through the second material and the fibers are oriented in a same direction within the second material. The propeller blade is anisotropic and includes sections of the fibers.

Anti-icing stacks for protecting an aerodynamic surface are described. In some embodiments, an anti-icing stack includes an anti-icing layer, an elastomeric erosion protection layer, and an additional layer. The erosion protection layer is disposed between the anti-icing layer and the additional layer. The additional layer has a thickness greater than the thickness of the erosion protection layer and a tensile modulus of no more than the tensile modulus of the erosion protection layer. The additional layer may be a foam adhesive layer.

A propeller blade having a blade body including a blade base, a blade tip, a pressure side surface, and, a suction side surface. Each of the pressure side surface and the suction side surface extend between the blade base to the blade tip. An end plate is provided on the blade body. The end plate is exposed to an airflow and positioned at the blade base. The end plate projects outwardly of at least a portion of one of the pressure side surface and the suction side surface.

A propeller blade comprises a root, a tip distal from the root, a trailing edge extending from the root to the tip, a trailing edge, e.g. foam, insert, a shell forming an outer surface of the propeller blade and a plurality of stitches of yam extending through two parts of the shell adjacent the trailing edge, wherein the yarns do not extend through the trailing edge insert.

An aviation turbine engine having at least one unducted rotary propeller having a plurality of blades, each blade including: a blade body made of composite material including fiber reinforcement densified by a matrix, the fiber reinforcement of the blade body presenting three-dimensional weaving, the body extending between a leading edge and a trailing edge, and a protective fitting for protecting the leading edge and made of composite material having fiber reinforcement densified by a matrix, the fitting being adhesively bonded onto the leading edge of the blade body, the fitting being formed from a dry fiber preform injection molded with a densifying resin, and a polyurethane film for providing protection against erosion covering the blade body and the fitting.

A method of manufacturing a spar for a propeller blade comprises forming a hollow inner core from a composite material, and then braiding carbon fibres around the inner core to form an outer spar structure. The hollow inner core may be formed using an inflatable bladder and a mould defining an outer shape of the spar. This construction avoids the need for a foam core to be provided within the spar.

A method of manufacturing a spar for a propeller blade comprises forming a hollow inner core from a composite material, and then braiding carbon fibres around the inner core to form an outer spar structure. The hollow inner core may be formed using an inflatable bladder and a mould defining an outer shape of the spar. This construction avoids the need for a foam core to be provided within the spar.

A foil, such as an aerofoil, having a leading edge and a trailing edge, of which at least a portion of one or both of the leading edge and trailing edge has a serrated profile comprising a plurality of adjoining teeth, each tooth having a tip point that represents a local maximum chord-wise extent of the tooth and, on each side span-wise of the tip point, a root point that represents a local minimum chord-wise extent of the tooth and at which the tooth adjoins a respective adjacent tooth, wherein the tooth edge profile varies with an ogee-like curve between tip point and root point such that the tooth is sharper in the neighbourhood of the tip point and in the neighbourhood of the root point than at locations in between.