Abstract: An rear fairing for a pylon supporting an aircraft turbojet engine forms an aerodynamic surface covering the base of the pylon. The rear fairing is elongated in a longitudinal direction and includes a floor arranged opposite the hot gases exiting the turbojet engine and side walls constituting aerodynamic surfaces. The floor and the side walls include ceramic matrix composite materials made from preforms formed by layers of superimposed warp and weft yarns, the preforms have interlayer weaving yarns connecting the layers to one another.

Abstract: A method for producing an acoustic attenuation panel from a composite material with a ceramic oxide matrix is provided that includes draping a plurality of plies having fibrous reinforcements including fibers of ceramic material in a mold to define a first skin, depositing blocks made of fugitive material on the first skin such that a space between two blocks is defined, and draping a second plurality of plies on a surface formed by the blocks such that a second skin is defined. Rounded corners of the blocks define radii for connecting the first and second skins with walls of a honeycomb core of the acoustic panel. The method further includes using a liquid medium to infiltrate the skins and spaces with a precursor of a ceramic phase, removing the liquid medium by evaporation or polymerization, and sintering to consolidate the ceramic oxide material and removal the fugitive material.

Abstract: The present disclosure concerns a porous body made of a ceramic-matrix composite material for an acoustic attenuation panel and a method of manufacturing the porous body. The porous body includes a plurality of interwoven ceramic fibers, a metal oxide matrix, and a plurality of channels interwoven with the ceramic fibers and interconnected together. The channels define at least one cavity. In one form, at least one channel is wrapped around a ceramic fiber. In another form, at least one ceramic fiber and at least one channel are twisted together. In yet another form, at least one channel is wrapped around a ceramic fiber and twisted with the ceramic fiber. The present disclosure also concerns an acoustic attenuation panel including the porous body and an aircraft propulsion unit having such a panel.

Abstract: An rear fairing for a pylon supporting an aircraft turbojet engine forms an aerodynamic surface covering the base of the pylon. The rear fairing is elongated in a longitudinal direction and includes a floor arranged opposite the hot gases exiting the turbojet engine and side walls constituting aerodynamic surfaces. The floor and the side walls include ceramic matrix composite materials made from preforms formed by layers of superimposed warp and weft yarns, the preforms have interlayer weaving yarns connecting the layers to one another.

Abstract: A device for fastening a downstream end of an air inlet on a fan casing of an aircraft turbojet engine nacelle is provided. The device includes an acoustic shroud, a first flange coupled to the fan casing, a second L-shaped flange having a base coupled to the acoustic shroud, and a collar linked to the first flange. The acoustic shroud extends from an upstream segment to a downstream segment which defines an inner skin and an outer skin that encloses an acoustic panel. The collar further includes a protrusion that extends from the outer skin to the downstream segment.

Abstract: A method for producing an acoustic attenuation panel from a composite material with a ceramic oxide matrix is provided that includes draping a plurality of plies having fibrous reinforcements including fibers of ceramic material in a mold to define a first skin, depositing blocks made of fugitive material on the first skin such that a space between two blocks is defined, and draping a second plurality of plies on a surface formed by the blocks such that a second skin is defined. Rounded corners of the blocks define radii for connecting the first and second skins with walls of a honeycomb core of the acoustic panel. The method further includes using a liquid medium to infiltrate the skins and spaces with a precursor of a ceramic phase, removing the liquid medium by evaporation or polymerization, and sintering to consolidate the ceramic oxide material and removal the fugitive material.

Abstract: The present disclosure relates to a method of repairing a damaged portion of a perforated skin of a panel using a doubler made of composite material which is designed to be applied to the damaged portion of the perforated skin. The method includes at least one step in which a sealing film is applied to the damaged portion of the perforated skin in order to temporarily seal the perforations in the skin, and a step in which the doubler is produced over the previously deposited sealing film.

Abstract: The present disclosure relates to a method for producing an acoustic attenuation panel having two outer skins made from a composite material with a ceramic matrix containing a fibrous reinforcement. The skins are assembled on each side of a central honeycomb core having walls forming acoustic cavities produced by at least partial electrochemical conversion of aluminum into aluminum oxide. The method includes inserting a fugitive filler material into the acoustic cavities, leaving an annular space free in each cavity, on each side against the skin, extending around the cavity, and a step of sintering the composite material, in which the fugitive material is removed and the spaces around the cavities are filled with the composite material.

Abstract: The present disclosure concerns a porous body made of a ceramic-matrix composite material for an acoustic attenuation panel and a method of manufacturing the porous body. The porous body includes a plurality of interwoven ceramic fibers, a metal oxide matrix, and a plurality of channels interwoven with the ceramic fibers and interconnected together. The channels define at least one cavity. In one form, at least one channel is wrapped around a ceramic fiber. In another form, at least one ceramic fiber and at least one channel are twisted together. In yet another form, at least one channel is wrapped around a ceramic fiber and twisted with the ceramic fiber. The present disclosure also concerns an acoustic attenuation panel including the porous body and an aircraft propulsion unit having such a panel.

Abstract: The present disclosure relates to a method of repairing a damaged portion of a perforated skin of a panel using a doubler made of composite material which is designed to be applied to the damaged portion of the perforated skin. The method includes at least one step in which a sealing film is applied to the damaged portion of the perforated skin in order to temporarily seal the perforations in the skin, and a step in which the doubler is produced over the previously deposited sealing film.

Abstract: A device for fastening a downstream end of an air inlet on a fan casing of an aircraft turbojet engine nacelle is provided. The device includes an acoustic shroud, a first flange coupled to the fan casing, a second L-shaped flange having a base coupled to the acoustic shroud, and a collar linked to the first flange. The acoustic shroud extends from an upstream segment to a downstream segment which defines an inner skin and an outer skin that encloses an acoustic panel. The collar further includes a protrusion that extends from the outer skin to the downstream segment.