Composite aerofoils

A composite aerofoil may include an aerofoil body defining a leading edge and a trailing edge, wherein the body comprises a composite material including a plurality of relatively higher-modulus reinforcement elements, a plurality of relatively tougher polymer-based reinforcement elements, and a matrix material substantially encapsulating the plurality of relatively higher-modulus reinforcement elements and the plurality of relatively tougher polymer-based reinforcement elements. The plurality of relatively higher-modulus reinforcement elements are different from the plurality of relatively tougher polymer-based reinforcement elements. The disclosure also describes techniques for forming composite aerofoils.