Patent ID: 7503273

Claim:
A method for the manufacture of a dry preform having a predetermined three-dimensional shape, the preform being intended for reinforcing a composite structural member of an aircraft and comprising continuous reinforcing fibers held together by a line of stitching, the method comprising the steps of: depositing tapes of continuous filaments and stitching said tapes together to form an underlying layer of continuous reinforcing fibers; depositing further tapes of continuous filaments on said underlying layer of previously deposited and stitched continuous filaments, and stitching said further tapes to said underlying layer; and cyclically depositing and stitching still further tapes of continuous filaments on the previously deposited and stitched layers, until a three-dimensional dry preform is obtained, said dry preform constituted by a succession of layers each formed by tapes of continuous filaments stitched together, wherein the filaments in each layer are deposited so as to be oriented and distributed according to a predetermined scheme.