Patent ID: 8844872
Filing Date: 2014-09-30
Classification: B29C,B29L,B64C,Y02T,Y10T

Abstract:
1. An aerofoil comprising a pair of skins which form low pressure and high pressure surfaces of the aerofoil; and a pair of spars which join the skins, wherein one of the skins and at least one of the spars are formed by a composite structure comprising a first section; a second section; and a curved corner joining the first section to the second section, the structure comprising a stack of fibre-reinforced plies, the stack including: a. a first external ply which runs from the first section into the second section round an inside of the corner; b. a second external ply which runs from the first section into the second section round an outside of the corner; c. a first internal ply which is sandwiched between the first and second external plies, runs from the first section into the second section round the corner, and is dropped off inside the second section so that more of the internal ply is located within the first section than within the second section; and d. a second internal ply which is sandwiched between the first and second external plies, runs from the second section into the first section round the corner, and is dropped off inside the first section so that more of the second internal ply is located within the second section than within the first section; wherein the structure has an increased thickness where the first and second internal plies overlap, and wherein the external plies are continuous plies which are not dropped off in either the skin or the spars.