Abstract: A first laminated body is worked to form a second laminated body, the first laminated body being formed by laminating prepregs including reinforcing fibers and resin, the second laminated body including a flat portion and a wavy portion, the flat portion being located at at least one of side edge portions of the second laminated body, the wavy portion being located at a portion adjacent to the side edge portion and extending along a longitudinal direction. An intermediate product is formed from the second laminated body by a forming die such that the flat portion becomes a bent portion that is an inside portion whose circumferential length is shorter in a curved portion, and the wavy portion becomes a bent portion that is an outside portion whose circumferential length is longer in the curved portion.

Abstract: An aircraft structure (such as a T-shaped structure, a convex structure, a curved structure, or the like) includes: a laminated structure including composite-material layers that are laminated; and wherein the composite material aircraft structure is a three-dimensional structure that includes at least one of a standing structure, a convex structure, or a curved structure. The composite-material layers include at least a composite-material layer in which a reinforced fiber is a single continuous fiber, wherein the single continuous fiber includes a partial slit region. When a thickness of a flat-plate formed body including a same laminated structure as the aircraft structure but not including the three-dimensional structure, is defined as a reference thickness, the aircraft structure includes a thin plate region which has a thickness that is smaller than the reference thickness while maintaining the laminated structure.

Abstract: A core according to one aspect of the present disclosure is a core that is inserted into a space between a skin and a stringer in a step of integrally molding the skin and the stringer, the skin including fiber-reinforced resin, the stringer having a hat-shaped section that is open toward the skin. The core includes: a first die that extends along a longitudinal direction of the stringer and contacts the skin; and a second die that extends along the longitudinal direction of the stringer and is located at an opposite side of the skin across the first die. The second die includes a material that is softer than the first die. The second die includes a slit perpendicular to the longitudinal direction of the stringer.

Abstract: A core according to one aspect of the present disclosure is a core that is inserted into a space between a skin and a stringer in a step of integrally molding the skin and the stringer, the skin including fiber-reinforced resin, the stringer having a hat-shaped section that is open toward the skin. The core includes: a first die that extends along a longitudinal direction of the stringer and contacts the skin; a second die that extends along the longitudinal direction of the stringer, is adjacent to the first die, and contacts the skin; and a third die that extends along the longitudinal direction of the stringer, is located at an opposite side of the skin across the first die and the second die, and contacts both the first die and the second die.

Abstract: A first laminated body is worked to form a second laminated body, the first laminated body being formed by laminating prepregs including reinforcing fibers and resin, the second laminated body including a flat portion and a wavy portion, the flat portion being located at at least one of side edge portions of the second laminated body, the wavy portion being located at a portion adjacent to the side edge portion and extending along a longitudinal direction. An intermediate product is formed from the second laminated body by a forming die such that the flat portion becomes a bent portion that is an inside portion whose circumferential length is shorter in a curved portion, and the wavy portion becomes a bent portion that is an outside portion whose circumferential length is longer in the curved portion.

Abstract: A composite-material aircraft structure includes: a laminated structure formed by laminating composite-material layers; and a curved structure having a circumferential length difference in a longitudinal direction. The laminated structure is maintained in the entire part including the curved structure. In each of the composite-material layers, the reinforced fiber is constituted by a single continuous fiber not including a joint portion and includes a partial slit portion and a notch portion that is the slit portion in an open state.

Abstract: An aircraft structure (such as a T-shaped structure, a convex structure, a curved structure, or the like) includes: a laminated structure including composite-material layers that are laminated; and wherein the composite material aircraft structure is a three-dimensional structure that includes at least one of a standing structure, a convex structure, or a curved structure. The composite-material layers include at least a composite-material layer in which a reinforced fiber is a single continuous fiber, wherein the single continuous fiber includes a partial slit region. When a thickness of a flat-plate formed body including a same laminated structure as the aircraft structure but not including the three-dimensional structure, is defined as a reference thickness, the aircraft structure includes a thin plate region which has a thickness that is smaller than the reference thickness while maintaining the laminated structure.