Abstract: The stiffeners of a composite material panel may be protected by a structural section having a configuration absorbing edge impacts without propagation of impact energy to the protected structure. Each composite panel with protected parallel stiffeners has a multiply front face coming to an edge and extending between two lateral flanks of outside plies, symmetrically relative to a median plane (Pm). A device for protecting each stiffener includes a structural section that caps the stiffener symmetrically relative to this median plane (Pm). This structural section consists of an upper section formed above the edge and configured to envelop a space above the edge, a lower section framing the lateral flanks by longitudinal walls (Pi) fastened to these flanks, and an intermediate section bearing at least partially on the edge via transverse walls (Pb) so as to minimize the propagation of impact forces to the lower section.

Abstract: The stiffening frames (14) of an aircraft fuselage (2) remain continuous while passing through an upper panel (5) of the wing box and extend over the ribs (3) situated in that box. The overall mechanical strength of the assembly is improved, despite the notches it is necessary to make in the panel (5).

Abstract: The stiffening frames (14) of an aircraft fuselage (2) remain continuous while passing through an upper panel (5) of the wing box and extend over the ribs (3) situated in that box. The overall mechanical strength of the assembly is improved, despite the notches it is necessary to make in the panel (5).

Abstract: A removable plate and a flange that occupies a hole in a panel. The flange has the particular feature of taking up compressive force to which the panel is subjected in its plane, perpendicularly to the hole. The weight of the device used to equip the hole is reduced, and the mechanical behavior of the panel at the position of the hole is improved.

Abstract: A self-stiffened panel of preimpregnated composite. The panel is of a type including a base skin on one side of which are added and placed side-by-side U-shaped stiffeners of which the parts connecting the branches of the U are flattened against the skin, with an interfacing structure between the adjoining branches of two adjacent stiffeners The interfacing structure is a nail having a nail-head comprised of a cord of filling resin. The nail is formed from a band with a rectangular cross-section whose edge, on the skin side, is directly in contact with the adjoining surface of the skin. The nail-head is comprised of two half-nail-heads placed symmetrically in the angle formed between the skin and the nail.

Abstract: A self-stiffened panel of preimpregnated composite. The panel is of a type comprised of a base skin on one side of which are added and placed side-by-side U-shaped stiffeners of which the parts connecting the branches of the U are flattened against said skin, with an interfacing structure between the adjoining branches of two adjacent stiffeners The interfacing structure is a nail having a nail-head comprised of a cord of filling resin, the nail formed from a band with a rectangular cross-section whose edge, on the skin side, is directly in contact with the adjoining surface of said skin. The nail-head is comprised of two half-nail-heads placed symmetrically in the angle formed between the skin and the nail.

Abstract: A removable plate and a flange that occupies a hole in a panel. The flange has the particular feature of taking up compressive force to which the panel is subjected in its plane, perpendicularly to the hole. The weight of the device used to equip the hole is reduced, and the mechanical behavior of the panel at the position of the hole is improved.