The invention relates to a method for manufacturing a box-shaped monolithic structure with a cavity by curing a fiber-reinforced prepreg material. The method comprises using two or more elongated and internally hollow support tools which have a complementary form to that of the cavities to be manufactured, and a composition based on reinforcement material and polymer suitable to allow the passage from a rigid state to a flexible elastomeric state and vice versa in response to heating/cooling down. In the rigid state, the support tools allow the direct lamination of the prepreg material on their external walls and are configured to set the flexible elastomeric state at a temperature lower than the curing temperature and higher than 50° C. During the curing operation, the curing pressure is applied both outside the structure being formed and inside the support tools, whose walls have become flexible, to push on the prepreg material to be cured.

The invention relates to a method for manufacturing a box-shaped monolithic structure with a cavity by curing a fiber-reinforced prepreg material. The method comprises using two or more elongated and internally hollow support tools which have a complementary form to that of the cavities to be manufactured, and a composition based on reinforcement material and polymer suitable to allow the passage from a rigid state to a flexible elastomeric state and vice versa in response to heating/cooling down. In the rigid state, the support tools allow the direct lamination of the prepreg material on their external walls and are configured to set the flexible elastomeric state at a temperature lower than the curing temperature and higher than 50° C. During the curing operation, the curing pressure is applied both outside the structure being formed and inside the support tools, whose walls have become flexible, to push on the prepreg material to be cured.

Additive and subtractive manufacturing (e.g. 3D Printing) is used to form aeroelastic airfoils with control surface region(s) having conventional rib/spar structural topologies and a continuous skin (e.g smooth surface) formed over the entire outer surface of the airfoil. The control surface is moved with internal actuators resulting in a “morphing” airfoil as the skin stretches to follow the moving structure of the control surface region. The airfoil can include a plurality of different material moduli and geometric featuring to balance the appropriate control of stiffness with topological requirements.

Additive and subtractive manufacturing (e.g. 3D Printing) is used to form aeroelastic airfoils with control surface region(s) having conventional rib/spar structural topologies and a continuous skin (e.g smooth surface) formed over the entire outer surface of the airfoil. The control surface is moved with internal actuators resulting in a “morphing” airfoil as the skin stretches to follow the moving structure of the control surface region. The airfoil can include a plurality of different material moduli and geometric featuring to balance the appropriate control of stiffness with topological requirements.

A method for manufacturing an aircraft leading edge panel, includes a step of overmoulding a coating onto a sheet positioned in a cavity of a mould, which cavity is delimited by a shaping surface which exhibits an optimized surface finish. The coating includes, after the overmoulding step, an exterior face which corresponds to the exterior face of the panel that is to be obtained and which exhibits an optimized surface finish conferred by the shaping surface of the mould. A panel may be obtained using this method and a leading edge includes at least one such panel. Because of the optimized surface finish of the exterior surface thereof, the panel contributes to extending the regions of laminar flow.

A method for manufacturing an aircraft leading edge panel, includes a step of overmoulding a coating onto a sheet positioned in a cavity of a mould, which cavity is delimited by a shaping surface which exhibits an optimized surface finish. The coating includes, after the overmoulding step, an exterior face which corresponds to the exterior face of the panel that is to be obtained and which exhibits an optimized surface finish conferred by the shaping surface of the mould. A panel may be obtained using this method and a leading edge includes at least one such panel. Because of the optimized surface finish of the exterior surface thereof, the panel contributes to extending the regions of laminar flow.

Methods and related structures to splice two sizes of cores in a manner to directly interface the facets of the cells and avoid the common practice of using fillers, casting materials, and expanding adhesives is useful to optimize the specific strength of the design and minimize the weight while maximizing the load carrying capability of the structure and to allow the core to vent moisture and other gasses.

In one aspect, there is a composite skin for a tiltrotor aircraft including a first skin having a periphery defined by a forward edge, an aft edge, and outboard ends; a second skin; and a honeycomb core disposed between the first skin and the second skin, the honeycomb core comprised of a plurality of honeycomb panels positioned along the longitudinal axis of the first skin, the plurality of honeycomb panels having an array of large cells, each cell having a width of at least 1 cm; wherein the second skin and the honeycomb core have an outer perimeter within the periphery of the first skin.

In one aspect, there is a composite skin for a tiltrotor aircraft including a first skin having a periphery defined by a forward edge, an aft edge, and outboard ends; a second skin; and a honeycomb core disposed between the first skin and the second skin, the honeycomb core comprised of a plurality of honeycomb panels positioned along the longitudinal axis of the first skin, the plurality of honeycomb panels having an array of large cells, each cell having a width of at least 1 cm; wherein the second skin and the honeycomb core have an outer perimeter within the periphery of the first skin.

An example method of manufacturing a wing includes providing a wing frame. The wing frame includes a primary spar, a drag spar, a plurality of transverse frame elements having at least one spar joiner, and a plurality of mounting elements. The primary spar is coupled to the drag spar via the at least one spar joiner. The method further includes placing the wing frame into a mold, wherein the mold defines a shape of the wing. The method also includes injecting the mold with an air-filled matrix material, such that the air-filled matrix material substantially encases the wing frame and fills the defined shape of the wing, and such that the plurality of transverse frame elements provide torsional rigidity to the wing.