Abstract: A dual-purpose bulkhead structure functions to support normal aircraft operational loads and to absorb energy in a controlled manner during a crash. An integral fuel tank comprises a fuel compartment and a crashworthy flexible fuel cell. The fuel compartment includes two dual-purpose bulkheads and crushable foam disposed between the sides of the fuel cell and the bulkheads and sides of the fuel compartment. The foam limits fuel pressure loads on fuel compartment bulkheads and sides during a crash, thereby preventing their failure.

Abstract: An energy absorber is provided. The energy absorber includes a thin panel (78) formed of composite materials (84) for reacting compression forces in the plane of the panel (78) between two opposed edges thereof. The panel (78) is constructed to resist overall bending failure when force is applied to the opposite edges. The energy absorber further includes force receiving structure (90, 92) for receiving forces directly to one of the edges and for receiving forces to the opposite edge of the panel (78) to initiate local folding parallel to the other edge for progressing crushing and local folding of the panel (78).

Abstract: High velocity impact landing forces are attenuated in apparatus (10) utilizing an energy absorbing tube (12) of composite fibrous material, that is, a fiber reinforced plastic. The energy absorbing tube (12) is disposed in force transmitting relation between an anvil (14) disposed at one end and structure (16) for applying a force to the opposite end of the tube (12) to provide force attenuating apparatus. The tube (12) is progressively crushed onto the anvil (14) by the force applying structure (16) to dissipate energy. The force attenuating apparatus (10) is used in an energy absorbing seat (20) to provide occupant protection against high impact forces. Other uses of the force attenuating apparatus (10) is in a landing gear mechanism (76) and a vehicle bumper system (89).