Abstract: A landing gear door system for a landing gear compartment includes a door pivotable about a pivot pin configured for disposition in a longitudinal direction on an airframe, and a mechanism configured to rotate the door about the pivot pin between a closed position, in which an outer surface of the door panel is configured to provide aerodynamic continuity with an outer aircraft skin of the airframe, and an open position, in which the door is rotated into the landing gear compartment and an opening is exposed. The door has a door panel rigidly connected with an arm such that the door panel and arm generally form a V-shape as viewed in the longitudinal direction.

Abstract: Described are novel composite structural panels and methods of forming such panels. In some examples, a method comprises wrapping a mandrel with a composite tape to form a composite tube. This wrapping operation allows forming composite tubular structures with any cross-sectional profiles defined by the mandrel. The wrapping is also used to control the fiber orientations in the composite tubular structures. The composite tube is then cut into composite tubular structures. In some examples, the composite tube is partially cured prior to the cutting, which allows removal of the mandrel while preserving the shape of the composite tube. This cutting operation allows forming composite tubular structures with different lengths, shapes, and orientations of the ends. The composite tubular structures are disposed on a support structure and are bonded to each other. In some examples, this bonding operation also involves final curing of the composite tubular structures.

Abstract: A landing gear door system for a landing gear compartment includes a door pivotable about a pivot pin configured for disposition in a longitudinal direction on an airframe, and a mechanism configured to rotate the door about the pivot pin between a closed position, in which an outer surface of the door panel is configured to provide aerodynamic continuity with an outer aircraft skin of the airframe, and an open position, in which the door is rotated into the landing gear compartment and an opening is exposed. The door has a door panel rigidly connected with an arm such that the door panel and arm generally form a V-shape as viewed in the longitudinal direction.

Abstract: Described are novel composite structural panels and methods of forming such panels. In some examples, a method comprises wrapping a mandrel with a composite tape to form a composite tube. This wrapping operation allows forming composite tubular structures with any cross-sectional profiles defined by the mandrel. The wrapping is also used to control the fiber orientations in the composite tubular structures. The composite tube is then cut into composite tubular structures. In some examples, the composite tube is partially cured prior to the cutting, which allows removal of the mandrel while preserving the shape of the composite tube. This cutting operation allows forming composite tubular structures with different lengths, shapes, and orientations of the ends. The composite tubular structures are disposed on a support structure and are bonded to each other. In some examples, this bonding operation also involves final curing of the composite tubular structures.

Abstract: A hat-shaped stringer includes wrap of at least one composite ply which includes cap portion and first flange which extends from a first side of the cap portion and second flange which extends from a second side of the cap portion, wherein the cap portion defines a recess positioned between the first and second flanges. Further included is a first composite wall which extends in a first direction along a first plane within the recess, wherein the first plane intersects the cap portion and intersects a skin positioned between the first and second flanges to which first and second flanges are secured and opposing sides of the first composite wall are spaced apart from the cap portion. First composite wall is connected to a second composite wall, which extends along the cap portion, are a portion, for example, of a triangular formation having radial portions.

Abstract: A hat-shaped stringer includes a wrap of at least one composite ply which includes a cap portion and a first flange which extends from a first side of the cap portion and a second flange which extends from a second side of the cap portion, wherein the cap portion defines a recess positioned between the first flange and the second flange. Further included is a first composite wall which extends in a first direction along a first plane within the recess, wherein the first plane intersects the cap portion and opposing sides of the first composite wall are spaced apart from the cap portion.