AIRCRAFT FUSELAGE SECTION

Abstract

An aircraft fuselage section extending along a longitudinal direction including: a fuselage structure comprising a plurality of frames; a floor connected to the fuselage structure; a cushioning element arranged on the floor, and a crash absorption assembly between the fuselage structure and the floor, wherein the crash absorption assembly includes first absorption elements and second absorption elements distributed along the longitudinal direction, wherein the first absorption elements and the second absorption elements are configured to dissipate and distribute energy; and wherein the first absorption elements are each arranged at a position corresponding to a frame of the fuselage structure and the second absorption elements are each arranged at a position between successive frames of the fuselage structure.

Claims

1. An aircraft fuselage section extending along a longitudinal direction, the aircraft fuselage section comprising: a fuselage structure comprising a plurality of frames; a floor connected to the fuselage structure; a cushioning element arranged on the floor, and a crash absorption assembly between the fuselage structure and the floor, wherein the crash absorption assembly includes first absorption elements and second absorption elements distributed along the longitudinal direction, wherein the first absorption elements and the second absorption elements are configured to dissipate and distribute energy; and wherein the first absorption elements are each arranged at a respective position corresponding to respective one of the frames of the fuselage structure and the second absorption elements are each arranged at a respective position between successive ones of the frames of the fuselage structure.

2. The aircraft fuselage section according to claim 1, further comprising at least one fuel storage tank arranged over and supported by the cushioning element.

3. The aircraft fuselage section according to claim 2, further comprising a gap between the fuel storage tank and the cushioning element.

4. The aircraft fuselage section according to claim 2, wherein the aircraft fuselage section further comprises a protective layer between the fuel storage tank and the cushioning element.

5. The aircraft fuselage section according to claim 4, wherein the protective layer is an elastomeric material.

6. The aircraft fuselage section according to claim 2, wherein the aircraft fuselage section further comprises an attaching fastener configured to attach the at least one fuel storage tank to the fuselage structure.

7. The aircraft fuselage section according to claim 1, wherein the attaching fastener comprises at least one of lugs, fittings, rods, band-clamps, or straps.

8. The aircraft fuselage section according to claim 1, wherein the first absorption elements and/or the second absorption elements are made of at least one of: a metallic material, an aluminum alloy or a titanium alloy, a composite material, an epoxy resin, or a foam.

9. The aircraft fuselage section according to claim 1, wherein the first absorption elements and/or the second absorption elements: are configured to undergo plastic deformation during a crash event; and/or are configured to collapse and/or tear out during a crash event.

10. The aircraft fuselage section according to claim 1, wherein the floor comprises: a panel, and supporting elements, wherein the supporting elements include a plurality of longitudinal beams extending in the longitudinal direction and a plurality of transversal beams extending perpendicularly to the longitudinal beams, and wherein the longitudinal beams and the transversal beams are connected to the fuselage structure.

11. The aircraft fuselage section according to claim 1, wherein the floor is a composite material and/or a metallic material.

12. The aircraft fuselage section according to claim 1, wherein the cushioning element comprises a plurality of cushioning portions configured to be assembled with each other.

13. The aircraft fuselage section according to claim 1, wherein the cushioning element is concave-shaped.

14. The aircraft fuselage section according to claim 1, wherein the cushioning element comprises at least one of: a foam cushion, a permanently inflatable or expanded panel, a balloon or a temporarily inflatable structure.

15. The aircraft fuselage section according to claim 1, further comprising: a substantially cylindrical upper shell configured to enhance fuel tank storage capacity, and a substantially vertical elliptical lower shell configured to enhance crashworthiness capabilities of the fuselage structure to transfer the compression loads arisen during the crash event.

16. An aircraft comprising the aircraft fuselage section according to claim 1.

17. An aircraft fuselage comprising: a skin extending circumferentially around an interior of the aircraft fuselage; frames covered and supporting the skin, wherein the frames extend around the interior of the aircraft and the frames are each arranged in a respective plane substantially perpendicular to a longitudinal axis of the aircraft fuselage, wherein the frames are spaced apart from each along the longitudinal axis; a floor in the interior and supported by the frames; a fuel tank within the interior and supported by the floor, wherein the fuel tank is configured to store liquid hydrogen; a deformable cushion on the floor and between the fuel tank and the floor, wherein the cushion abuts a lower outer surface of the fuel tank along an entire length of the fuel tank, and a crash absorption assembly between the frames and the floor, wherein the crash absorption assembly is aligned with the fuel tank along a direction perpendicular to the longitudinal axis, and the crash absorption assembly includes first absorption elements and second absorption elements distributed along the longitudinal direction, wherein the first absorption elements and the second absorption elements are configured to dissipate and distribute energy; and wherein the first absorption elements are each aligned with a respective one of the frames and the second absorption elements are each between successive ones of the frames along the longitudinal direction.

Description

DESCRIPTION OF THE DRAWINGS

[0091] These and other characteristics and advantages of the invention will become clearly understood in view of the detailed description of the invention which becomes apparent from embodiments of the invention, given just as examples and not being limited thereto, with reference to the drawings.

[0092] FIGS. 1 is a schematic representation of a longitudinal section view of an aircraft fuselage section according to an embodiment of the invention.

[0093] FIG. 2 is a more detailed schematic representation of a longitudinal section view of an aircraft fuselage section according to the embodiment of the invention of FIG. 1.

[0094] FIGS. 3 to 5 are schematic representations of a cross-sectional views of an aircraft fuselage section according to an embodiment of the invention.

[0095] FIG. 6 is a schematic representation of a cushioning element according to an embodiment of the invention.

[0096] FIG. 7 is a schematic representation of a floor according to an embodiment of the invention.

[0097] FIG. 8 is a schematic representation of the attaching fastener according to an embodiment of the invention.

[0098] FIG. 9 is a schematic representation of an aircraft comprising an aircraft fuselage section according to an embodiment of the invention.

DETAILED DESCRIPTION

[0099] FIGS. 1 to 5 show a schematic representations of a longitudinal section view of an aircraft fuselage section (1) according to an embodiment of the invention. In particular, the aircraft fuselage section (1) shows a fuselage structure comprising a plurality of frames (2) covered by a skin (9). The interior (10) of fuselage structure includes a floor (3) supported by the frames and thereby connected to the fuselage structure. Cushioning element (4) is arranged on the floor (3) and located below a first fuel storage tank (11). The aircraft fuselage section (1) of FIG. 1 also depicts crash absorption assembly (5) arranged between the fuselage structure and the floor (3).

[0100] The crash absorption assembly (5) comprises a plurality of first absorption elements (5.1) and a plurality of second absorption elements (5.2) distributed along the longitudinal direction (X). The plurality of first absorption elements (5.1) and the plurality of second absorption elements (5.2) being configured for dissipating and distributing energy in order to limit the transfer of energy to the first fuel storage tank (11) in case of a crash plane.

[0101] As shown in FIG. 1, the first absorption elements (5.1) are each arranged at a position corresponding to a frame (2) and the second absorption elements (5.2) are each arranged at a position between successive frames (2) of the fuselage structure.

[0102] The first absorption elements (5.1) may be strips, bars or other deformable structures that have a width corresponding to a width of a frame to which the first absorption element corresponds. The first absorption elements may be mounted to the corresponding frame and have upper surfaces which support the cushioning element. The first absorption elements may be aligned in a plane perpendicular to the longitudinal direction (X).

[0103] The second absorption elements (5.2) extend substantially along the longitudinal direction (X) and are in gaps between successive ones of the frames. The second absorption elements (5.2) may substantially fill or fill a majority of the gaps between successive frames in a region between the cushioning element and the skin.

[0104] In the particular embodiment depicted in FIG. 1, the aircraft fuselage section (1) also comprises a second fuel storage tank (12) which is free of cushioning element or crash absorption assembly because, in this configuration of the tanks, the second fuel storage tank is less prone to crash. In other embodiments, not shown in the set of figures, the area where the second fuel storage tank (12) is arranged or even the whole aircraft fuselage section (1) is fully protected by cushioning element and/or crash absorption assembly. In other embodiments, the aircraft fuselage section (1) does not include more than one fuel storage tank.

[0105] In an embodiment, the first absorption elements (5.1) and/or the second absorption elements (5.2) are formed of materials that include one or more of: metallic, aluminum alloys or titanium alloys; and/or composite material, such as epoxy resin, foam or any combination thereof; or any combination thereof.

[0106] In an embodiment, the first absorption elements (5.1) and/or the second absorption elements (5.2) are configured to undergo plastic deformation during a crash event and/or are configured to collapse and/or tear out during a crash event.

[0107] FIG. 2 shows a more detailed view of a portion of the elements located below the first fuel storage tank (11) of the aircraft fuselage section (1). In particular, FIG. 2 depicts the layout of the floor (3), the cushioning element (4) and the crash absorption assembly (5). As shown in this figure, the crash absorption assembly (5) are arranged in such a way that the first absorption elements (5.1) are disposed at a position matching with the frames (2) of the fuselage structure and the second absorption elements (5.2) are arranged in between frames (2), that is in between first absorption elements (5.1). In other words, there is a sequential distribution of first absorption elements (5.1) and second absorption elements (5.2) along the longitudinal direction (X).

[0108] In an embodiment, the set-up of the elements of the invention is responsible for the fuel storage tank (11) getting in contact with the cushioning element (4) before the fuselage structure does with the crash absorption elements (5). In another embodiment, these elements enter in contact at the same time in case of a crash event or in an opposite way with respect to the previous embodiment, that is the fuselage structure enters first in contact with the crash absorption elements (5) and then the fuel storage tank (11) gets in contact with the cushioning element (4). In an embodiment, the mentioned elements are arranged with the appropriate gaps there between to define the desired sequence of contacts.

[0109] In the embodiment shown in FIG. 2, the crash absorption assembly (5) extend further the length of the cushioning element (4) and further the length of the fuel storage tank (11).

[0110] Also in the embodiment shown in FIG. 2, the cushioning element (4) length matches with the length of the first fuel storage tank (11). In other embodiments, the cushioning element (4) extends further the length of the first fuel storage tank (11) in order to provide additional protection to other elements located in the surrounding area of said first fuel storage tank (11).

[0111] FIGS. 3 to 5 show a schematic representation of a cross-sectional view of an aircraft fuselage section (1) according to an embodiment of the invention.

[0112] FIG. 3 depicts a cross-sectional view of the aircraft fuselage section (1), wherein the cross-sectional view shows the aircraft fuselage section (1) at a plane traversing a first absorption element (5.1), that is, the cross-section is performed along one frame (2) of the fuselage structure. In this embodiment, a first fuel storage tank (11) is arranged over the cushioning element (4). In this embodiment, the cushioning element (4) and the first fuel storage tank (11) are separated by a protective layer (6). As shown, the cushioning element (4) is arranged on the floor (3) and a first absorption element (5.1) is arranged between the fuselage structure and the floor (3), that is, the first absorption element (5.1) is arranged between the frame (2) of the fuselage structure and the floor.

[0113] FIG. 4 depicts a cross-sectional view of the aircraft fuselage section (1), wherein the cross-sectional view shows the aircraft fuselage section (1) at a plane traversing a second absorption element (5.2), that is, the cross-section is performed at a location between two successive frames (2) of the fuselage structure. In this figure, the aircraft fuselage section (1) includes a protective layer (6) located between the fuel storage tank (11) and the cushioning element (4). The cushioning element (4) is arranged on the floor (3) and the second absorption element (5.2) is arranged between the fuselage structure and the floor (3).

[0114] In other embodiments, not shown in FIGS. 3 to 5, the fuel storage tank (11) is arranged such that there is a gap between the fuel storage tank (11) and the cushioning element (4). In these embodiments, where a gap is located between the fuel storage tank (11), the aircraft fuselage section may optionally include a protective layer (6).

[0115] In an embodiment, the protective layer (6) is made of an elastomeric material.

[0116] In some embodiments, the plurality of frames of the fuselage structure has a rounded shape as shown in FIGS. 3 and 4.

[0117] FIG. 5 shows the same embodiment of the aircraft fuselage section (1) as shown in FIG. 3, but in the aircraft fuselage section (1) of FIG. 5 a deformation of the frame (2) has occurred due to a crash event. In this figure, it is shown the effect of compression loads which arise on the fuselage structure during said crash event, leading to a significant deformation of the fuselage structure.

[0118] In an embodiment, the aircraft fuselage section comprises a substantially cylindrical upper shell configured to maximize fuel tank storage capacity and a substantially vertical elliptical lower shell to enhance the crashworthiness capabilities of the fuselage structure to transfer the compression loads arisen during the crash event.

[0119] FIG. 6 depicts an embodiment of the cushioning element (4) where said cushioning element (4) has a plurality of cushioning portions (4.1) configured to be assembled with each other. In other embodiments, the cushioning element (4) has only one portion.

[0120] In other embodiments not shown, the cushioning element (4) is made of one portion which covers the length required.

[0121] In an embodiment, as shown in FIG. 6, the cushioning element (4) is concave-shaped. In some embodiments, the cushioning element (4) is concave-shaped in order to fit to the substantially cylindrical shape of a fuel storage tank as the one shown in the embodiments of FIG. 1, 3, 4 or 5.

[0122] In an embodiment, the cushioning element (4) comprises foam, permanent inflatable means or temporary inflatable means.

[0123] In an embodiment where the cushioning element (4) comprises foam, wherein the foam has different ranges of density to adapt the stiffness mechanical properties of the cushioning element (4) to a desired behavior. In that sense, the cushioning element (4) helps minimizing the stress level generated over the fuel storage tank surface area during the braking off. In some particular embodiments, the cushioning element (4) is fully made of foam. In other particular embodiments, only the outer surface of the cushioning element (4) is made of foam. In both particular embodiments, the cushioning element (4) has a specific thickness which allows said cushioning element (4) to enter in direct contact with the fuel storage tank in case of a crash event.

[0124] In an embodiment where the cushioning element (4) comprises permanent inflatable means, said permanent inflatable means are made of pneumatic material such as inflatable panels. The permanent inflatable means are filled to the required pressure in order to ensure the function of loads transfer to the floor (not shown in this figure) while minimizing the stress level generated over the fuel storage tank surface area. In an embodiment, the permanent inflatable means are filled with spheres, or other geometries, made of soft materials.

[0125] In an embodiment, both foam and permanent inflatable means can be combined as an embodiment. In an embodiment, the foam has a low stiffness value in order to protect the fuel storage tank surface area and the permanent inflatable means have a low to medium stiffness value. In some further embodiments, the inflatable means also includes an airbag with a regulation valve in order to control overpressure and absorb kinetic energy, for example, by gas expansion.

[0126] In an embodiment where the cushioning element (4) comprises temporary inflatable means such as airbags, said temporary inflatable means only inflates in case of a crash event through a pyrotechnic system or similar.

[0127] FIG. 7 shows an embodiment of the floor (3), where said floor (3) includes a panel (3.1) and supporting elements (3.2, 3.3), the supporting elements (3.2, 3.3) comprising a plurality of longitudinal beams (3.2) extending in the longitudinal direction (X) and a plurality of transversal beams (3.3) extending perpendicularly to the longitudinal beams (3.2). Also, even if not shown in said FIG. 7, the longitudinal beams (3.2) and the transversal beams (3.3) are connected to the fuselage structure.

[0128] In an embodiment, the floor (3) is made of composite material and/or metal.

[0129] FIG. 8 shows an embodiment of an aircraft fuselage section (1) comprising attaching fastener (7) configured to attach the first fuel storage tank (11) to the fuselage structure, for example to a frame of the fuselage structure.

[0130] As shown in FIG. 8, the aircraft fuselage section (1) includes a cushioning element (4) arranged on the floor (3). Although not visible in FIG. 8, crash absorption assembly are arranged between the floor (3) and the bottom part of the fuselage structure of the aircraft fuselage section (1).

[0131] In an embodiment, the attaching fastener (7) comprises lugs, fittings, rods, band-clamps, straps or any combination thereof. In the particular embodiment depicted in FIG. 8, the attaching fastener (7) are straps or band-clamps arranged around the fuel storage tank (11) for coupling said tank to the aircraft fuselage section (1).

[0132] In the embodiment shown in FIG. 8, the aircraft fuselage structure (1) comprises two safety belts (8) configured to retain the fuel storage tank (11) in case of a crash event. In the embodiment shown, the safety belts (8) are implemented as two straps or band-clamps attached to the fuselage structure, for example attached to frames of the fuselage structure.

[0133] FIG. 9 shows an embodiment of an aircraft (20) comprising an aircraft fuselage section (1) according to an embodiment of the invention.

[0134] While at least one exemplary embodiment of the present invention(s) is disclosed herein, it should be understood that modifications, substitutions and alternatives may be apparent to one of ordinary skill in the art and can be made without departing from the scope of this disclosure. This disclosure is intended to cover any adaptations or variations of the exemplary embodiment(s). In addition, in this disclosure, the terms comprise or comprising do not exclude other elements or steps, the terms a or one do not exclude a plural number, and the term or means either or both, unless the disclosure states otherwise.

[0135] Furthermore, characteristics or steps which have been described may also be used in combination with other characteristics or steps and in any order unless the disclosure or context suggests otherwise. This disclosure hereby incorporates by reference the complete disclosure of any patent or application from which it claims benefit or priority.