A long frame is provided with: a plurality of frame members that have a longitudinal direction and a short direction, have a first flange part folded along a folding line extending along the longitudinal direction, and are arranged close to an inner peripheral surface of a surface plate along an array direction; and a plurality of first connecting parts that connect each of the plurality of first flange parts to the surface plate. The frame is further provided with at least one of a second connecting part that connects second flange parts to each other and a third connecting part that joins together end surfaces of a pair of frame members arranged adjacent to each other in the array direction to connect the pair of frame member arranged adjacent to each other.

A vibration damper for an additively manufactured structure includes a structure at least partially formed with an additive manufacturing technique. Also included is a damping element embedded within the structure at an internal location of the structure. A method of damping vibration of an additively manufactured component is provided. The method includes additively manufacturing a structure. The method also includes embedding at least one damping element within the structure at an internal location of the structure.

Pre-impregnated composite material (prepreg) that can be cured/molded to form aerospace composite parts. The prepreg includes carbon reinforcing fibers and an uncured resin matrix. The resin matrix includes an epoxy component that is a combination of a hydrocarbon epoxy novolac resin and a trifunctional epoxy resin and a tetrafunctional epoxy resin. The resin matrix includes polyethersulfone as a toughening agent and a thermoplastic particle component that includes a mixture of polyamide particles and polyimide particles.

Systems are provided for fabricating a preform for a fuselage section of an aircraft. The system includes advancing a series of arcuate mandrel sections in a process direction through an assembly line, laying up fiber reinforced material onto the arcuate mandrel sections via layup stations, uniting the series of arcuate mandrel sections into a combined mandrel; and splicing the fiber reinforced material laid-up onto the arcuate mandrel sections.

The aim of the invention is to propose an edging method that is quick, effective, easy to implement and makes it possible to obtain a lightweight panel. To this end, the aim of the invention is a method for sealingly edging a composite panel comprising; *a step (a) of providing a composite panel of redefined thickness having two planar faces and a side to be edged, and of providing a sealing strip made from a polymer material having a width greater than the thickness of the composite panel, and comprising a first face, referred to as the “inner” face, and a second face, referred to as the “outer” face, in reference to the position of use of same: *a step (b) of applying the strip and an adhesive to the side and to a peripheral portion of the planar faces of the composite panel in such a way that the adhesive is located between the composite panel and the inner face of the strip, which sealingly protects the composite panel against dust, foreign bodies and the absorption of moisture.

A manufacturing method of a reinforced structure includes a step of preparing a stringer that has a fiber exposed surface, a step of disposing an electrically conductive protection member on the fiber exposed surface to cover at least a part of the fiber exposed surface, a step of arranging the stringer on a skin having an uncured resin component, and a step of curing the skin after the arranging. The electrically conductive protection member includes a composite material made of combination of a resin component and an electrically conductive fiber component. The step of curing includes curing the skin and the electrically conductive protection member simultaneously. The manufacturing method can prevent edge glow without increasing the number of production steps.

Described herein are stringer assemblies, such as blade stringers, and methods of forming thereof. A stringer assembly comprises a first fabric composite stiffener, a second fabric composite stiffener, and an intermediate tape composite stiffener, disposed between and connected to each of the first and second stiffeners. Using three separate components allows forming sharp bends, eliminating voids and gap fillers, and adding new features, such as edge reinforcements. Each of the first and second fabric composite stiffeners comprises a web portion, a flange portion, and a curved portion, positioned between the web and flange portions. The web portions surround and are attached to the intermediate tape composite stiffener and, in some examples, include tapered-out edges for additional rigidity. The flange portions are attached to the composite base. The curved portions conform to the flared-out edges of the intermediate tape composite stiffener, which extends and connects to the composite base.

Described herein are methods and systems for forming composite stringer assemblies or, more specifically, for shaping composite charges while forming these stringer assemblies. A system comprises a bladder, having a bladder core, and a bladder skin. The bladder core is formed from foam. The bladder skin is formed from an elastic material and encloses the bladder core. When a composite stringer assembly is formed, the bladder is positioned over a charge base. The charge base later becomes a stringer base, such as a fuselage section or a wing skin. A charge hat is then positioned over the bladder and is conformed to the bladder. A combination of the bladder skin and the bladder core provides support during this forming operation and later while the stringer assembly is cured. In some examples, the bladder core is collapsible for the removal of the bladder from the cavity of the stringer assembly.

A method of manufacturing an arc-shaped fiber composite component includes forming a preform with a planar fiber layer arrangement formed along an arc and having an outer edge assigned to a convex outer side of the arc. The outer edge is formed with gaps extending into the arrangement in such a manner that a contour of the gaps is formed at least in sections near a target contour of a respective recess to be provided in the component. The preform is formed such that a first region of the arrangement, adjacent to the outer edge and extending substantially in the direction of the arc, is bent or angled relative to a second region of the arrangement, adjacent to the first region remote from the outer side of the arc. The gaps that the preform has prior to reshaping merge into recesses of the formed preform and remain open.

An aircraft skin panel includes a laminated composite layer and a ground plane coupled to the composite layer, wherein the ground plane is an electrically conductive elastic thermoplastic.