Method of forming a composite structure comprising a flange

A method of manufacturing a composite structure comprising a main body and a flange which is positioned along a first edge of the main body and which has a wall portion which is connected to the main body through a first bend and a lip portion which is connected to the wall portion through a second bend in the opposite direction to the first bend, the method comprising the steps of:

• laying-up a curved preform on a mould, wherein the preform does not have the first and second bends and comprises a first part which corresponds to the main body of the composite structure and a second part which corresponds to the flange of the composite structure, the second part of the preform has a proximal portion which corresponds to the wall portion of the flange and a distal portion which corresponds to the lip portion of the flange, the first and second parts of the preform comprise a plurality of plies and uni-directional ply material extends from the first part of the preform to the distal portion of the second part of the preform;
• forming the flange by advancing movable portions of the mould to form the proximal portion of the second part of the preform to create the first bend and by forming the distal portion of the second part of the preform around the advancing movable portions of the mould to create the second bend;
• and
• curing resin in the formed flange and the first part of the preform;
• wherein the movable mould portions are blocks which are spaced apart along the first edge and which, in the forming step, are moved from a retracted configuration to a radially outwardly-advanced configuration with respect to the curved preform.