Provided are methods of forming stiffened stringer panels with integrated plank structures. A skin member having an inner surface is provided. A plank is positioned onto the inner surface of the skin member. The plank extends from a first side to a second side, and each laminate ply of the set of layered laminate plies is sized to form a geometric profile for each of the first side and the second side. Each laminate ply of the set of layered laminate plies is arranged to extend from the first side to the second side. A stringer is placed onto a support tool. The support tool, and the stringer thereon, is positioned upon an uppermost laminate ply of the set of layered laminate plies. The skin member, the plank, and the stringer are joined.

Systems and methods for a caul plate for an irregular surface. One embodiment is a caul plate for co-curing or co-bonding a first composite part and a second composite part. A body of the caul plate includes a lower surface to face a top surface of the first composite part, a reference edge to locate the second composite part on the first composite part, and an upper surface that is opposite to the lower surface. The lower surface includes one or more bends to match one or more slopes in the top surface of the first composite part. The one or more bends correspond with ply changes in the first composite part.

A fuselage structure for an aircraft has a frame structure, which extends in a circumferential direction and has a first connecting section and a second connecting section, which is arranged spaced apart from the first connecting section, a reinforcing structure, which extends between the first and the second connecting sections and is connected respectively to the first and the second connecting sections, an outer shell, which is secured on an outer side of the reinforcing structure, and an inner shell, which is secured on an inner side of the reinforcing structure. The reinforcing structure has a profiled cross section when viewed in a longitudinal direction extending transversely to the circumferential direction and, together with the inner shell and the outer shell, forms a plurality of channels, which are adjacent to one another in the circumferential direction and each extend in the longitudinal direction.

A reinforced sandwich panel, including two skin panels; a foam core disposed between the two skin panels; and an expandable framework disposed within the foam core.

A reinforced sandwich panel, including two skin panels; a foam core disposed between the two skin panels; and an expandable framework disposed within the foam core.

An aircraft structure protected from collisions with foreign objects includes a first support proximate to an aircraft structure root; first sheets attached to the first support to form a first leading edge portion of the aircraft structure; a second support proximate to an outer end of the aircraft structure; second sheets attached to the second support to form a second leading edge portion; and a door including one or more ribs disposed between the first and second supports and configured to give shape to a third leading edge portion of the aircraft structure; and third sheets, attached to the ribs to form the third portion of the leading edge; wherein the first support, the first sheets, the second support, the second sheets, the one or more ribs, and the third sheets are disposed to mitigate damage from a foreign object collision by absorbing kinetic energy from a collision.

An aircraft structure protected from collisions with foreign objects includes a first support proximate to an aircraft structure root; first sheets attached to the first support to form a first leading edge portion of the aircraft structure; a second support proximate to an outer end of the aircraft structure; second sheets attached to the second support to form a second leading edge portion; and a door including one or more ribs disposed between the first and second supports and configured to give shape to a third leading edge portion of the aircraft structure; and third sheets, attached to the ribs to form the third portion of the leading edge; wherein the first support, the first sheets, the second support, the second sheets, the one or more ribs, and the third sheets are disposed to mitigate damage from a foreign object collision by absorbing kinetic energy from a collision.

An apparatus for securing a panel to a structure is provided. In one embodiment, the fastener includes a fastener having a fastener head and a threaded tail, and the fastener may be disposed through a structure and an external panel. The apparatus also includes a retainer housing positioned on the fastener head, where the retainer housing is detached from the fastener. A spring engaging the fastener and the retainer housing is also included within the retainer housing.

An apparatus for securing a panel to a structure is provided. In one embodiment, the fastener includes a fastener having a fastener head and a threaded tail, and the fastener may be disposed through a structure and an external panel. The apparatus also includes a retainer housing positioned on the fastener head, where the retainer housing is detached from the fastener. A spring engaging the fastener and the retainer housing is also included within the retainer housing.

A stiffened structural component for an aircraft includes a first material sheet with a first surface, and at least one elongate bulge that bulges out in a direction transverse to the first surface in order to stiffen the structural component, wherein each of the at least one bulge comprises two edges that extend along the first surface, wherein a continuous bulging surface extends between the edges, and wherein the bulges are formed integrally into the first material sheet through pressing.