Patent attributes
A composite blade (26) comprises a three-dimensional arrangement of reinforcing fibres (58) and a matrix material (60) infiltrated around the three-dimensional arrangement of woven reinforcing fibres (60). The three-dimensional arrangement of woven reinforcing fibres (58) defines a plurality of cavities (56) within the aerofoil (28). The composite blade (26) comprises an aerofoil portion (38) and a root portion (36). The aerofoil portion (38) comprises a leading edge (44), a trailing edge (46), a concave pressure surface wall (50), a convex suction surface wall (52) and a tip (48). The aerofoil portion (36) comprises a plurality of webs (54) extending between, and being secured to, the concave pressure surface wall (50) and the convex suction surface wall (52) to produce a Warren girder structure. The three-dimensional arrangement of woven reinforcing fibres (58) are arranged to produce the concave pressure surface wall (50), the convex suction surface wall (52) and the plurality of webs (54). The matrix material (60) is an organic resin and the reinforcing fibres (58) comprise carbon fibres.