An insulation insert comprises a hollow cylinder formed of a closed cell foam, a first adhesive layer on a first face of the hollow cylinder, a flange of the closed cell foam extending from the hollow cylinder, and a second adhesive layer on a second face of the flange.

A shielded, multi-layer heatshield material for hypersonic flight applications includes an ablative/insulative structure having a thickness and providing both thermal insulation and a first ablation resistance, and a separate shield layer bound to an outer surface of the ablative/insulative structure, the shield layer being thinner than the ablative/insulative structure while providing a second higher ablation resistance greater than the first ablation resistance. In one arrangement the ablative/insulative structure includes a carbon/carbon composite layer attached to a syntactic carbon foam layer, using carbon fiber stitched loops for reinforcement, and the shield layer is a carbide outer layer. In another arrangement the ablative/insulative structure includes a silica composite layer attached to a silica insulative foam layer, using stitched loops for reinforcement, and the shield layer is a ceramic outer layer.

A shielded, multi-layer heatshield material for hypersonic flight applications includes an ablative/insulative structure having a thickness and providing both thermal insulation and a first ablation resistance, and a separate shield layer bound to an outer surface of the ablative/insulative structure, the shield layer being thinner than the ablative/insulative structure while providing a second higher ablation resistance greater than the first ablation resistance. In one arrangement the ablative/insulative structure includes a carbon/carbon composite layer attached to a syntactic carbon foam layer, using carbon fiber stitched loops for reinforcement, and the shield layer is a carbide outer layer. In another arrangement the ablative/insulative structure includes a silica composite layer attached to a silica insulative foam layer, using stitched loops for reinforcement, and the shield layer is a ceramic outer layer.

The present disclosure provides a method of allocating shared radio resources in a spectrum shared system (SSS), the method including: obtaining, by a system controller of the SSS, identification information from at least one radio service device of the SSS and a node unit of a distributed antenna system (DAS); determining, by the system controller of the SSS, whether the at least one radio service device interoperates with the DAS based on the identification information; and allocating, by the system controller of the SSS, the shared radio resources to the at least one radio service device and the DAS, respectively, based on a result of the determining of interoperating.

The present disclosure provides a method of allocating shared radio resources in a spectrum shared system (SSS), the method including: obtaining, by a system controller of the SSS, identification information from at least one radio service device of the SSS and a node unit of a distributed antenna system (DAS); determining, by the system controller of the SSS, whether the at least one radio service device interoperates with the DAS based on the identification information; and allocating, by the system controller of the SSS, the shared radio resources to the at least one radio service device and the DAS, respectively, based on a result of the determining of interoperating.

An additively manufactured noise attenuation panel for a structure within an aircraft structure includes a plurality of unit cells, each including a central body interconnected via a plurality of tubes extending from the central body. The noise attenuation panel may include an increasing wall thickness in a desired direction. A layers of unit cells may be manufactured in a twisted orientation with respect to an immediately adjacent layer of unit cells. Layers of unit cells may be manufactured in a rounded or bent orientation with respect to a central axis. The noise attenuation panel may further comprise a disk and a blended transition located at the interface between the disk and an interior surface of a unit cell.

An additively manufactured noise attenuation panel for a structure within an aircraft structure includes a plurality of unit cells, each including a central body interconnected via a plurality of tubes extending from the central body. The noise attenuation panel may include an increasing wall thickness in a desired direction. A layers of unit cells may be manufactured in a twisted orientation with respect to an immediately adjacent layer of unit cells. Layers of unit cells may be manufactured in a rounded or bent orientation with respect to a central axis. The noise attenuation panel may further comprise a disk and a blended transition located at the interface between the disk and an interior surface of a unit cell.

An acoustic absorber for a gas turbine engine includes a back sheet, a face sheet spaced apart from the back sheet and defining a plurality of perforations, and a core layer positioned between the back sheet and the face sheet and comprising a plurality of cells. The core layer comprises an outer wall extending between the back sheet and the face sheet to define an outer boundary of at least one cell of the plurality of cells and an inner wall positioned within the outer boundary to divide the at least one cell of the plurality of cells into an outer damping volume and an inner damping volume, the inner damping volume being at least partially surrounded by the outer damping volume.

An aircraft fuselage portion extending in a general longitudinal direction and comprising a fuselage structure comprising annular frames and a flat floor. The fuselage portion also comprises struts perpendicular to the floor in a nominal position and extending from the floor to a frame. Each strut comprises, in the vicinity of at least one of the ends thereof, a detachable link so that the strut can be moved relative to the fuselage structure or separated from the fuselage structure to temporarily grant access to a triangle area located between the frames, the floor and the struts in the nominal position. This allows access to be granted to the area in which the ducts must be installed in the aircraft, in particular, in the form of sets of ducts assembled prior to their installation in the fuselage.

A formation method is provided during which a cellular core is provided. The cellular core includes a plurality of cavities that include a first cavity. Each of the cavities extends through the cellular core. A metal substrate is disposed within the first cavity. The metal substrate is electroplated to form a septum within the first cavity. The septum is bonded to the cellular core.