Patent ID: 8864076

Claim:
An elongate structural member for use in an aerospace structure, wherein the structural member is made from composite material comprising a multiplicity of layers, the structural member has a foot and a web extending from the foot, the structural member defines along a part of its length: a first surface on the foot being shaped to abut the aerospace structure, a second surface on the foot being opposite the first surface, a third surface on or in the web being at the same layer in the composite material as the first surface, a fourth surface on the web being on the same side of the structural member as the second surface, a fifth surface interposed between and joining the first and third surfaces, and a sixth surface interposed between and joining the second and fourth surfaces, for any cross-section of the structural member at any point along a part of the length of the structural member, the section being taken across a plane having its normal axis parallel to the length of the structural member, at least part of the fifth surface is inclined at an acute angle to the adjacent part of the first surface and at least part of the fifth surface is inclined at an acute angle to the adjacent part of the third surface, and wherein the geometry of the structural member varies along said part of its length so that with increasing distance in a given direction along the length of the structural member the first surface is displaced in a direction towards the second surface as the width of the fifth surface decreases, whereby the risk of causing, during fabrication of the elongate structural member, undesirable creasing, stressing or stretching of composite material layers in a region in which the geometry of the elongate structural member varies with increasing distance along its length is reduced.