Abstract: A method for producing a closed-section portion of an aircraft wherein a strain gauge is glued on a first face of a flat tape that, in turn, is fastened on a face of a tool comprising a rigid elongated body covered by an extensible sack. The tool supporting the tape is arranged in a cavity of an aircraft structure. A vacuum is then created to obtain the expansion of the vacuum sack and perform the pressure gluing of the tape onto a wall of said cavity. The tool is subsequently extracted from the cavity. Upon conclusion of these operations, the tape is integrally fastened onto a wall of the cavity so that any deformation applied to this wall is transmitted to said strain gauge.

Abstract: A method of manufacturing a wing structure includes laying a plurality of layers of preimpregnated material on a first mould half and on a second mold half so as to form a first fresh skin and a second fresh skin of the wing structure. A plurality of layers of preimpregnated material are laid in succession on a shaped apparatus to form a fresh leading edge skin of the wing structure. Fresh spars of preimpregnated material are formed. A wedgelike body of expanded plastics material is formed, this body being designed to be interposed between the first and second skins at the trailing edge of the wing structure. The fresh spars are positioned in a coordinated way on the first fresh skin, removable support members also positioned next to the spars. The second mold half is turned over on to the first mold half so as to position the second fresh skin on the spars and the supports, to produce a fresh wing structure. The fresh wing structure is subjected to a polymerization cycle, using a vacuum bag.

Abstract: A method for producing a closed-section portion of an aircraft wherein a strain gauge is glued on a first face of a flat tape that, in turn, is fastened on a face of a tool comprising a rigid elongated body covered by an extensible sack. The tool supporting the tape is arranged in a cavity of an aircraft structure. A vacuum is then created to obtain the expansion of the vacuum sack and perform the pressure gluing of the tape onto a wall of said cavity. The tool is subsequently extracted from the cavity. Upon conclusion of these operations, the tape is integrally fastened onto a wall of the cavity so that any deformation applied to this wall is transmitted to said strain gauge.

Abstract: A method of manufacturing a curved structural element made of composite material has a complex, open cross-section the structural element is formed by the assembly of components made of composite material. A plurality of flat, fresh components are prepared, each component being constituted by a flat layer of curved fibres previously infused with resin, combined with a pre-impregnated layer with straight fibres. Hot-forming of the flat, raw components is then performed. The hot-formed, fresh components are then assembled in accordance with a predetermined sequence on a polymerization tool. The tool includes a shaped, inflatable device astride which a C-shaped raw component is deposited. Finally, the fresh components assembled on the tool are subjected to a polymerization cycle in an autoclave. The inflatable device is inflated by the pressure produced in the autoclave to apply a predetermined pressure from the inside of the C-shaped fresh component.

Abstract: A tool for the infusion of a resin into a preform made of fiber material includes a mould which can be closed around the preform and in the body of which at least one inlet duct is formed to allow resin to be injected into the mould so that the resin can be infused into the preform. At least one reservoir which can contain the resin, is also formed in the body of the mould and is connected to the at least one inlet duct. The mould can be inserted in an autoclave and the reservoir is configured to permit the transfer of the resin from the reservoir to the inlet duct under the effect of the temperature and of the pressure that are produced in the autoclave, thus allowing the resin to be injected into the mould.

Abstract: A method of manufacturing a curved element made of composite material includes: preparing at least one dry, flat reinforcing layer with curved fibers. A resin film is combined with the dry, flat reinforcing layer, and heat and pressure are applied in controlled manner to bring about the infusion of the resin into the reinforcing layer and to obtain at least one layer of pre-infused material. At least one prepreg layer is prepared with straight fibers impregnated with resin compatible with the resin of the pre-infused material. The layer of pre-infused material and the prepreg layer are superimposed on one another to obtain a layered structure. The layered structure, arranged on a shaped support tool is subjected to a polymerization cycle to obtain the curved element.

Abstract: A method of manufacturing a Z-section component from composite material uses a mold having a convex mold portion and a concave mold portion. The method includes the preparation of a vacuum bag for a polymerization cycle, including the covering the fresh component with a layer of peel ply formed from a plurality of strips of peel ply and fixing the layer of peel ply perimetrically to the mold using an adhesive tape. A line of sealant is positioned perimetrically above the adhesive tape around the fresh component and a separator film is positioned above the layer of peel ply so as to cover the layer of peel ply and the perimetric line of sealant. A ventilation textile is placed perimetrically on the mold, the textile having an aperture which is positioned so as to leave uncovered an underlying part substantially coinciding with the fresh component. A vacuum bag is applied for the polymerization cycle.

Abstract: A method of manufacturing a curved structural element made of composite material has a complex, open cross-section the structural element is formed by the assembly of components made of composite material. A plurality of flat, fresh components are prepared, each component being constituted by a flat layer of curved fibres previously infused with resin, combined with a pre-impregnated layer with straight fibres. Hot-forming of the flat, raw components is then performed. The hot-formed, fresh components are then assembled in accordance with a predetermined sequence on a polymerization tool. The tool includes a shaped, inflatable device astride which a C-shaped raw component is deposited. Finally, the fresh components assembled on the tool are subjected to a polymerization cycle in an autoclave. The inflatable device is inflated by the pressure produced in the autoclave to apply a predetermined pressure from the inside of the C-shaped fresh component.

Abstract: A tool for the infusion of a resin into a preform made of fibre material includes a mould which can be closed around the preform and in the body of which at least one inlet duct is formed to allow resin to be injected into the mould so that the resin can be infused into the preform. At least one reservoir which can contain the resin, is also formed in the body of the mould and is connected to the at least one inlet duct. The mould can be inserted in an autoclave and the reservoir is configured to permit the transfer of the resin from the reservoir to the inlet duct under the effect of the temperature and of the pressure that are produced in the autoclave, thus allowing the resin to be injected into the mould.

Abstract: A method of manufacturing a wing structure includes laying a plurality of layers of preimpregnated material on a first mould half and on a second mold half so as to form a first fresh skin and a second fresh skin of the wing structure. A plurality of layers of preimpregnated material are laid in succession on a shaped apparatus to form a fresh leading edge skin of the wing structure. Fresh spars of preimpregnated material are formed. A wedgelike body of expanded plastics material is formed, this body being designed to be interposed between the first and second skins at the trailing edge of the wing structure. The fresh spars are positioned in a coordinated way on the first fresh skin, removable support members also positioned next to the spars. The second mold half is turned over on to the first mold half so as to position the second fresh skin on the spars and the supports, to produce a fresh wing structure. The fresh wing structure is subjected to a polymerization cycle, using a vacuum bag.

Abstract: A method of manufacturing a curved element made of composite material includes: preparing at least one dry, flat reinforcing layer with curved fibres. A resin film is combined with the dry, flat reinforcing layer, and heat and pressure are applied in controlled manner to bring about the infusion of the resin into the reinforcing layer and to obtain at least one layer of pre-infused material. At least one prepreg layer is prepared with straight fibres impregnated with resin compatible with the resin of the pre-infused material. The layer of pre-infused material and the prepreg layer are superimposed on one another to obtain a layered structure. The layered structure, arranged on a shaped support tool is subjected to a polymerization cycle to obtain the curved element.

Abstract: A method of manufacturing a Z-section component from composite material uses a mould having a convex mould portion and a concave mould portion. The method includes the preparation of a vacuum bag for a polymerization cycle, including the covering the fresh component with a layer of peel ply formed from a plurality of strips of peel ply and fixing the layer of peel ply perimetrically to the mould using an adhesive tape. A line of sealant is positioned perimetrically above the adhesive tape around the fresh component and a separator film is positioned above the layer of peel ply so as to cover the layer of peel ply and the perimetric line of sealant. A ventilation textile is placed perimetrically on the mould, the textile having an aperture which is positioned so as to leave uncovered an underlying part substantially coinciding with the fresh component. A vacuum bag is applied for the polymerization cycle.

Abstract: For the manufacture of a dry preform intended for reinforcing a composite structural member of an aircraft, a digitally controlled automatic machine similar to an embroidery machine deposits and stitches successive layers of continuous reinforcing fibres. In each layer the fibres are oriented and distributed according to a predetermined scheme. A preform is obtained having a predetermined three-dimensional shape in which the reinforcing fibres are distributed and oriented an in optimum manner.

Abstract: For the manufacture of a dry preform intended for reinforcing a composite structural member of an aircraft, a digitally controlled automatic machine similar to an embroidery machine deposits and stitches successive layers of continuous reinforcing fibres. In each layer the fibres are oriented and distributed according to a predetermined scheme. A preform is obtained having a predetermined three-dimensional shape in which the reinforcing fibres are distributed and oriented an in optimum manner.