There is provided a laminated composite structure having improved impact damage resistance and improved strength. The laminated composite structure has a plurality of stacked layers of a composite material. The plurality of stacked layers have one or more interlaminar corrugations formed within the plurality of stacked layers. Each interlaminar corrugation has a substantially sinusoidal shaped profile, and has a depth and a length dependent on a size of the laminated composite structure formed. The laminated composite structure with the one or more interlaminar corrugations has improved strength and improved impact damage resistance at an exposed edge of the laminated composite structure, when the exposed edge is subjected to an impact force.

A duct stringer is disclosed including a structural member with a hat-shaped cross-section. The structural member has a crown, a pair of webs and a pair of feet. A channel member with a U-shaped cross-section has a base and a pair of flanges. The flanges of the channel member are co-cured to opposed inner faces of the webs of the structural member. The structural member and the channel member together provide a duct with a closed cross-section which is adapted to transport fluid, for instance in an aircraft wing to provide a vent function in an aircraft fuel system.

Methods and devices of fabricating a stringer for a vehicle. The stringer can be constructed from two charges that are formed together into the stringer. During fabrication, the charges are placed over support members with the ends of each charge extending over a die cavity. The charges are secured and a punch die forces the first ends into the die cavity forming blades of the stringer. The charges are secured thus tensioning the charges during the punch process.

A panel assembly with a panel and a stringer is disclosed. The stringer has a stringer foot and an upstanding stringer web. The stringer foot has a flange which extends in a widthwise direction between the stringer web and a lateral edge and in a lengthwise direction alongside the stringer web, and a foot run-out which extends between the flange and a tip of the stringer foot. The foot run-out is bonded to the panel at a foot run-out interface. Reinforcement elements, such as tufts, pass through the foot run-out interface into the panel. The reinforcement elements are distributed across the foot run-out interface in a series of rows including an end row nearest to the tip of the stringer foot and further rows spaced progressively further from the tip of the stringer foot. At least the end row has three or more of the reinforcement elements which are distributed along a polygonal curve.

A method for manufacturing a wing-box for aircraft comprises: arranging, on a curing surface, a first panel of composite material comprising a skin a plurality of longitudinal stringers, and arranging, on each stringer, a caul plate; arranging, on the first panel, pluralities of support inserts so that each support insert rests on a respective caul plate, and on the skin of the first panel, and arranging, on the first panel, a plurality of ribs of non-polymerized composite material, each rib comprising a plate, a first pair of flanges and a second pair of flanges arranged at opposed ends of the plate, and having openings on an edge of the plate, by placing the respective first pair of flanges on the first panel and the respective plurality of openings on the plurality of support inserts, and having the first panel and the plurality of ribs undergo a curing process in autoclave with vacuum bag.

A method for fabricating a central caisson of an aircraft wing including a frame formed from U-section crossmembers. Formation of at least one crossmember includes forming a stack comprising at least one layer of resin film applied to a layer of dry fibers, pressing this stack to confer on it a U-section form and such as to compress the layers thereof, and pre-polymerization and/or polymerization of the resin of the stack. The manipulated fiber layers are layers of dry fibers, such that manipulation thereof by an automated machine may be effected for a reasonable cost and at a high throughput. Deposition of resin films carried by removable leaves, i.e., of which one of the faces is not adhesive, likewise facilitates manipulation by an automated installation.

A method of fabricating a solid laminate stringer on a composite panel, including unspooling one or more composite layers onto the composite panel; compacting the one or more composite layers unspooled onto the composite panel; cutting the one or more composite layers unspooled onto the composite panel; and curing the one or more composite layers unspooled onto the composite panel, wherein the one or more composite layers are unspooled continuously along a length corresponding to a length of the solid laminate stringer.

A dam for use with a duct having a longitudinal axis. The dam employs a single piece insert having a first lateral flange and a second lateral flange configured to engage opposing interior lateral surfaces of the duct. The insert engages the duct in sealing contact in a seated position. The first and second lateral flanges are offset longitudinally along the longitudinal axis and joined with a curved wall having a curvature shaped to be received, with the insert oriented at an insert angle about a normal axis perpendicular to the longitudinal axis, in an aperture in the duct.

A trailing edge for a composite multispar integrated lifting surface includes a first C-shape composite form that includes a web and two flanges. The web forming a portion of the rear spar of a torsion box. The two flanges extending along a skin chordwise direction. A second C-shape composite form includes a web and two flanges. The web forms an auxiliary spar. The flanges extend along the skin chordwise direction. The first C-shape composite form and the second C-shape composite form forming a first auxiliary cell and a second cell. The first auxiliary cell is delimited by the first C-shape composite form and the second C-shape composite form. The second cell is an open cell delimited by the second C-shape composite form.

Prior to curing a composite workpiece assembly, an expandable element can be inserted into a cavity of the workpiece assembly. The expandable element is configured to expand when a predetermined change is produced in an attribute of the element. The attribute can be a temperature of the element. The element is expanded by producing the predetermined change, and the workpiece assembly is cured while the expanded element is in the cavity, so that the expanded element applies positive pressure to inner surfaces of the cavity during curing. The expanded element can be removed from the cavity after curing. The expanded element can comprise a plurality of expandable pellets.