Crashworthiness structure and method
AssigneePolitecnico Di Milano
InventorMarco Anghileri
Life of this patent
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Abstract
What is described is a locally yielding structure (1) with high energy absorption for aeronautical applications, the said structure being substantially closed and substantially rigid, characterized in that at least one wall (3) of the said substantially closed structure comprises at least one vent valve (8) which can be opened when a pressure exceeding a predetermined value is present within the substantially closed structure (1). In a particularly advantageous application, the invention is used in connection with a helicopter tank and enables the subfloor to be used to absorb energy by being deformed during any impact on the ground. The present invention is also advantageous for limiting the damage caused by explosions in an aircraft fuselage.
Claims31
A fuel tank positionable within a host aeronautical structure and having high energy absorption characteristics for aeronautical applications, the said fuel tank comprising:
- a substantially closed and substantially rigid main fuel tank comprising at least one lateral wall;
- at least one vent valve formed in the at least one lateral wall and which can be opened when a pressure exceeding a predetermined value is present within the substantially closed main fuel tank;
- a supplementary fuel tank configured to cooperate with the at least one lateral wall and adapted to receive fuel from said main fuel tank through said at least one vent valve when said at least one vent valve is open because of an overpressure within said main fuel tank;
- wherein said vent valve comprises a breakable membrane which is positioned to close a corresponding aperture, wherein said breakable membrane comprises a fragile material;
- and
- an aperture stiffener fixed to the at least one lateral wall, surrounding the at least one valve, and configured to provide rigidity reinforcement for the at least one lateral wall of the main fuel tank;
- wherein the aperture stiffener is in the form of a collar positioned around substantially only a circumference of the aperture of the vent valve.
A method of operating a substantially closed and substantially rigid main fuel tank positionable within a host aeronautical structure, the method comprising:
- providing at least one vent valve which can be opened when a pressure exceeding a predetermined value is present within the substantially closed main fuel tank, wherein said at least one vent valve is provided in at least one lateral wall of the main fuel tank;
- providing an aperture stiffener to surround the at least one valve and to provide rigidity reinforcement for the at least one lateral wall of the main fuel tank wherein the aperture stiffener is in the form of a collar positioned around substantially only a circumference of the aperture of the vent valve;
- forming a breakable membrane to comprise a material which is fragile;
- and
- when said at least one vent valve is open because of an overpressure within said main fuel tank, providing a supplementary fuel tank cooperating with the said at least one vent valve to receive fuel through said at least one vent valve.
Dependencies are inferred from the claim text.