Anti-icing stacks for protecting an aerodynamic surface are described. In some embodiments, an anti-icing stack includes an anti-icing layer, an elastomeric erosion protection layer, and an additional layer. The erosion protection layer is disposed between the anti-icing layer and the additional layer. The additional layer has a thickness greater than the thickness of the erosion protection layer and a tensile modulus of no more than the tensile modulus of the erosion protection layer. The additional layer may be a foam adhesive layer.

Embodiments are directed to systems and methods for creating a tubular composite structure. In one embodiment, a device comprises multiple layers of cured composite fabric bonded together to form a tubular composite structure, wherein alternating groups of the multiple layers comprise on-axis fabric and off-axis fabric. The tubular composite structure may form a spar for an aerodynamic component. The composite fabric may comprise one or more of carbon, fiberglass, or other composite materials, or a combination of materials. One or more stacks of the fabric wrap completely around the tubular composite structure, and other stacks of fabric may not wrap completely around the tubular composite structure.

An airfoil component assembly for an aircraft includes an additively manufactured flyaway tool including an infill support core and an interface sheet surrounding the infill support core, a spar formed from one or more layers of composite material disposed on the interface sheet of the flyaway tool and a skin formed from one or more layers of composite material disposed on the spar and the interface sheet of the flyaway tool. The flyaway tool, the spar and the skin form the airfoil component assembly for use by the aircraft in flight.

A method of making an aircraft blade is provided. The method comprises the steps of: assembling two or more fibre-reinforced thermoplastic composite parts into a blade assembly; and welding the fibre-reinforced thermoplastic composite parts together utilising an additional thermoplastic located at least at locations where the parts will abut when assembled. The additional thermoplastic has a melting or softening temperature lower than a melting temperature of each of the fibre-reinforced thermoplastic composite parts being assembled. The step of welding comprises heating the blade assembly to a temperature above the melting/softening temperature of the additional thermoplastic and below the melting temperature of each of the fibre-reinforced thermoplastic composite parts so as to melt/soften the additional thermoplastic and thereby weld the fibre-reinforced thermoplastic composite parts together to form the aircraft blade.

A system includes a mandrel having an exterior surface configured to receive composite material, a first end, and a second end opposite the first end, an end support coupled to the first end of the mandrel such that the mandrel is rotatable about an axis of rotation, and an intermediate support configured to support the mandrel between the first end and the second end such that at least a portion of the exterior surface is exposed while the mandrel is supported by the intermediate support, a vertical distance between the intermediate support and the axis of rotation defining a support distance, and the intermediate support being adjustable between a first position having a first support distance and a second position having a second support distance greater than the first support distance.

A method of repairing an aircraft component having a structural core surrounded by an exterior skin of composite material includes removing damaged material from the component to create a cavity therein that exposes an undamaged portion of the structural core, applying a septum comprising composite material to the undamaged portion of the structural core within the cavity such that an orientation of fibers in the septum matches an orientation of fibers in the exterior skin, placing a repair core onto the septum in the cavity such that cells of the repair core are in alignment with cells of the undamaged portion of the structural core, inserting a shim into the cavity along a perimeter of the repair core, applying a patch that covers the cavity to the exterior skin, and co-curing the septum, shim, and patch to bond the repair core in place within the cavity.

A composite laminate for connection to at least one attachment component in a load-introduction joint, said composite laminate comprising an opening that is adapted to receive a load-introduction component of said load-introduction joint, wherein a prefailure indication element is provided in the region of said opening, said prefailure indication element being modifiable by said load-introduction component in a prefailure mode of said load-introduction joint for indication of an impending function-affecting failure of said composite laminate. The invention is further related to a corresponding load-introduction component.

An airfoil component assembly for an aircraft includes an additively manufactured flyaway tool including an infill support core and an interface sheet surrounding the infill support core, a spar formed from one or more layers of composite material disposed on the interface sheet of the flyaway tool and a skin formed from one or more layers of composite material disposed on the spar and the interface sheet of the flyaway tool. The flyaway tool, the spar and the skin form the airfoil component assembly for use by the aircraft in flight.

A corrugated lift fan rotor is disclosed. In various embodiments, a rotor includes an upper skin, a lower skin, and an at least partly corrugated core encased between the upper skin and the lower skin. In some embodiments, the core comprises a composite material, such as carbon fiber reinforced polymer composite material, and includes an upper cap portion, a lower cap portion, and a web portion extending between the upper and lower cap portions.

A method of repairing an aircraft component having a structural core surrounded by an exterior skin of composite material includes removing damaged material from the component to create a cavity therein that exposes an undamaged portion of the structural core, applying a septum comprising composite material to the undamaged portion of the structural core within the cavity such that an orientation of fibers in the septum matches an orientation of fibers in the exterior skin, placing a repair core onto the septum in the cavity such that cells of the repair core are in alignment with cells of the undamaged portion of the structural core, inserting a shim into the cavity along a perimeter of the repair core, applying a patch that covers the cavity to the exterior skin, and co-curing the septum, shim, and patch to bond the repair core in place within the cavity.