a is a cross section of a blade similar to the blade of fig1 having a different distribution along the periphery of the parts with pultrusion strips fig2 b shows a plane view of a blade similar to the blade shown in cross section in fig2 a thus having a similar distribution along the periphery of the parts with pultrusion strips fig2 c is a photograph of the surface of the blade of fig2 a with the outer shell of composite material removed and the blade shown in cross section in fig1 has a layer comprised of 40 u00d7 40 millimetre strips of birch plywood 1 in alternating sequence with 6 u00d7 40 millimetre strips of a carbon fibre pultrusion 2 the layer 1 2 stretches along the central part of the blade between two c beams 3 4 of glass fibre web and synthetic resin composite denoted the le leading edge web 3 and the te travelling edge web 4 and replacing the central inner beam discussed previously the layer 1 2 is sandwiched between an inner layer and an outer layer 6 of glass epoxy skins that carry shear stress and promote the transverse stiffness of the blade the space defined between the upper and lower shell thus constituted by the birch plywood 1 and the carbon fibre pultrusion 2 and the le web 3 and the te web 4 is filled with a balsa wood core 7 the blade shown in fig2 a 2 b and 2 c are similar to the one shown in fig1 with the exception that the reinforcement of carbon fibre pultrusions 2 are situated near.