A noise attenuation element can be arranged for connection to an air directing structure such as a wing flap. The element has a non-uniform lattice density across at least a portion of the body of the element.

A noise attenuation element can be arranged for connection to an air directing structure such as a wing flap. The element has a non-uniform lattice density across at least a portion of the body of the element.

Systems, devices, and methods including a leading edge tubular member; an upper tubular member; a lower tubular member; one or more upper rib members connected between the leading edge tubular member and the upper tubular member; one or more lower rib members connected between the leading edge tubular member and the lower tubular member; a rigid sandwich shell disposed between the upper tubular member and the leading edge tubular member; and a sandwich shear web disposed between the upper tubular member and the lower tubular member; where the rigid sandwich shell and the sandwich shear web form a D-shape.

Systems, devices, and methods including a wing panel; a spar disposed in the wing panel, where the spar comprises: an upper cap; a lower cap; a honeycomb core connected between at least a portion of the upper cap and the lower cap; an inner face sheet; and an outer face sheet, where at least a portion of the honeycomb core is disposed between the inner face sheet and the outer face sheet.

Systems, devices, and methods including a wing panel; a spar disposed in the wing panel, where the spar comprises: an upper cap; a lower cap; a honeycomb core connected between at least a portion of the upper cap and the lower cap; an inner face sheet; and an outer face sheet, where at least a portion of the honeycomb core is disposed between the inner face sheet and the outer face sheet.

An airfoil system is provided that includes an airfoil. This airfoil includes a first exterior surface, a second exterior surface, a first airfoil segment and a second airfoil segment. The airfoil extends widthwise between the first exterior surface and the second exterior surface. The first airfoil segment includes first composite material and a receptacle. A base of the receptacle is embedded within the first composite material. The second airfoil segment includes second composite material and a key. A base of the key is embedded within the second composite material. The key is mated with the receptacle thereby attaching the second airfoil segment to the first airfoil segment.

An airfoil system is provided that includes an airfoil. This airfoil includes a first exterior surface, a second exterior surface, a first airfoil segment and a second airfoil segment. The airfoil extends widthwise between the first exterior surface and the second exterior surface. The first airfoil segment includes first composite material and a receptacle. A base of the receptacle is embedded within the first composite material. The second airfoil segment includes second composite material and a key. A base of the key is embedded within the second composite material. The key is mated with the receptacle thereby attaching the second airfoil segment to the first airfoil segment.

An airfoil system is provided that includes an airfoil. This airfoil includes a first exterior surface, a second exterior surface, a first airfoil segment and a second airfoil segment. The airfoil extends widthwise between the first exterior surface and the second exterior surface. The first airfoil segment includes first composite material and a receptacle. A base of the receptacle is embedded within the first composite material. The second airfoil segment includes second composite material and a key. A base of the key is embedded within the second composite material. The key is mated with the receptacle thereby attaching the second airfoil segment to the first airfoil segment.

An airfoil system is provided that includes an airfoil. This airfoil includes a first exterior surface, a second exterior surface, a first airfoil segment and a second airfoil segment. The airfoil extends widthwise between the first exterior surface and the second exterior surface. The first airfoil segment includes first composite material and a receptacle. A base of the receptacle is embedded within the first composite material. The second airfoil segment includes second composite material and a key. A base of the key is embedded within the second composite material. The key is mated with the receptacle thereby attaching the second airfoil segment to the first airfoil segment.

A method for assembling a box structure includes elementary parts assembled along an understructure of stiffeners and skins. The understructure and skins are made of composite material with a polymer matrix. The method includes sizing the box structure for the loads to which it is subjected and for a glued assembly. A map of the loads on the structure is obtained and a first load limit is defined depending on the probability of the structure being damaged. The understructure and the skins are assembled by gluing them. An additional layer is applied that covers the assembled elementary parts to areas of the assembled box structure where the first load limit is reached.