Aircraft fuselage section and aircraft

Abstract

The invention provides an aircraft fuselage section and an aircraft. The aircraft fuselage section includes a first fuel storage tank and a second fuel storage tank arranged in a tail tandem configuration. More specifically, the invention relates to an arrangement of said first and second tanks in which respective housings containing conduits are arranged in the same section of the fuselage and spaced apart between the first and second tanks, the conduits being configured for dispensing fuel to and from the interior of the tanks.

Description

Technical Field

[0001] The present invention belongs to the technical field of fuel storage systems in aircraft. In particular, the present invention provides an aircraft section comprising a first fuel storage tank and a second fuel storage tank arranged in a tail tandem configuration. Background Art

[0002] For environmental reasons, the challenge of reducing the use of fossil fuels must be increasingly faced. In this context, hydrogen produced based on renewable energy sources is a logical candidate for efficient energy supply. The high energy density of hydrogen makes it an emerging alternative fuel for aircraft applications.

[0003] In particular, hydrogen is an attractive fuel for high-altitude-short-range aircraft because it contains about 3 times more energy per kilogram than traditional hydrocarbon fuels. Therefore, in aircraft applications, the high specific energy of hydrogen may be a key contributing factor. However, practical problems have largely hindered its use. Although the specific energy of hydrogen is very high, the energy per unit volume is relatively low. Liquid hydrogen (LH2) improves its energy density relative to the gaseous form, while allowing the mass of the tank required to confine hydrogen therein to be reduced due to the low pressure in the liquid state. Compared with 40 g / l of gaseous hydrogen at 88K and 700 bar, liquid hydrogen at 20K and 1 bar pressure has a density of 70 g / l. Only cryogenically compressed hydrogen has a higher density, with a value of 80 g / l at 38K and 300 bar. According to these parameters, the liquefied cryogenic form allows effective storage at low pressure.

[0004] In this regard, LH2 cryogenic tanks (i.e. tanks configured to contain liquid hydrogen and to maintain the necessary conditions to keep hydrogen in a liquid state) are one of the key components of the structures of future generations of heavy-lift launch vehicles, space exploration structures, and new green aircraft. In aircraft, the biggest challenge is to develop systems to store hydrogen due to the need to reduce weight and have good thermal insulation and permeability.

[0005] A further challenge in the aircraft industry is to make optimal use of the available volume inside the aircraft for accommodating fuel storage elements as well as additional elements and equipment for fuel conditioning, maintaining optimal operating conditions and fuel distribution. Summary of the invention

[0006] The invention provides an aircraft fuselage section and an aircraft.

[0007] In a first inventive aspect, the present invention provides an aircraft fuselage section extending in a longitudinal direction, wherein the fuselage section comprises a first fuel storage tank and a second fuel storage tank, the first fuel storage tank and the second fuel storage tank being arranged in a tail tandem configuration such that the second tank is arranged continuously with respect to the first tank according to the longitudinal direction,

[0008] wherein the first tank comprises a first end portion oriented toward the second tank, and the second tank comprises a second end portion oriented toward the first tank, such that a fuselage section is defined between the first end portion of the first tank and the second end portion of the second tank,

[0009] The aircraft fuselage section further comprises:

[0010] a first housing disposed at a first end portion of the first tank, the first housing being configured to accommodate a conduit in fluid communication with an interior of the first tank, and

[0011] a second housing disposed at a second end portion of the second tank, the second housing being configured to accommodate a conduit in fluid communication with an interior of the second tank,

[0012] And among them,

[0013] the first shell extends from the first end portion of the first tank into the fuselage subsection,

[0014] The second shell extends from the second end portion of the second tank into the fuselage subsection, and

[0015] The first housing is spaced apart from the second housing according to a partition direction included in a plane perpendicular to the longitudinal direction.

[0016] Throughout this document, with respect to the term "first fuel storage tank", the term "first tank" will also be used to refer to such "first fuel storage tank". Similarly, with respect to the term "second fuel storage tank", the term "second tank" will also be used to refer to such "second fuel storage tank".

[0017] With regard to the first tank and the second tank, having more than a single tank in the same aircraft section provides various benefits, such as increased safety due to redundancy. In this sense, the presence of two tanks acts as an operational backup, which increases the reliability of the fuel storage capacity of the aircraft section in the event of a failure of one of the functions or components of one of the first tank or the second tank.

[0018] It will be appreciated that both tanks are configured to contain fuel therein. Preferably, both tanks are cryogenic tanks and are configured to contain liquid hydrogen (LH2) or any other suitable fuel used in the aircraft industry.

[0019] With respect to the first and second end portions of the respective first and second tanks, they are to be understood as portions of each tank which are located respectively at the rearmost position and the forwardmost position according to the longitudinal direction of the fuselage section.

[0020] More specifically, once the aircraft fuselage segment is realized as part of an aircraft, the longitudinal direction of the aircraft fuselage segment corresponds to the longitudinal axis of said aircraft, and the vertical plane is the plane defined by the pitch axis and the yaw axis of the aircraft (i.e. the horizontal axis and the vertical axis when considering straight cruising flight). In this respect, it should be understood that the frontmost part of the aircraft corresponds to the cockpit and the rearmost part of the aircraft corresponds to the tail cone. In this sense, it should be understood that the first end portion of the first tank is oriented rearwardly and the second end portion of the second tank is oriented forwardly.

[0021] Regarding the tandem configuration, the arrangement of the first and second tanks one after the other according to the longitudinal direction of the fuselage section makes it possible to optimize the cross section of the fuselage section intended to accommodate each of the first and second tanks. Thus, the total fuel volume in the fuselage section of the aircraft is also optimized.

[0022] According to the invention, there is a separation between the first tank and the second tank in the longitudinal direction. In this respect, the first end portion of the first tank and the second end portion of the second tank are arranged to be oriented in opposite directions, and the two tanks are arranged so that a predetermined distance is established between the first end portion of the first tank and the second end portion of the second tank. That is, the first end portion of the first tank is oriented towards the position of the second tank, and the second end portion of the second tank is oriented towards the position of the first tank, and a certain volume of the aircraft fuselage section is defined between the first end portion of the first tank and the second end portion of the second tank.

[0023] In this respect, the volume extends longitudinally along the distance defined between the two tanks and should be regarded as a subsection of the aircraft fuselage segment.

[0024] With regard to the first and second shells, which are arranged at the first end portion of the first tank and at the second end portion of the second tank, respectively, these shells are configured to accommodate conduits that are in fluid communication with the interior of the respective first tank or second tank. More specifically, inside these shells there may be a set of different pipes and / or valve systems for performing tasks such as refueling, supply of the main engine, distribution between different tanks, or ventilation of the tanks. It should be understood that such shells should be provided with the necessary passage means (i.e. openings), such as grooves or holes, for the pipes, which route the fuel from the tanks and route the fuel to the tanks.

[0025] Advantageously, the housing provides an enclosure extending from the respective tank, which enclosure acts as a safety layer to prevent any failure in the event of a fuel leak and to minimize the effects of thermal gradients between the tank and its external environment.

[0026] With regard to the arrangement of the first shell and the second shell relative to each other, the first shell extends from a first end portion of the first tank into the fuselage subsection, and the second shell extends from a second end portion of the second tank into the fuselage subsection, the first shell and the second shell being spaced apart from each other according to any direction defined in a plane perpendicular to the longitudinal direction. Said direction is herein referred to as the "separation direction".

[0027] The separation established between the first shell and the second shell increases the operational safety of an aircraft comprising the aircraft fuselage segment of the invention by preventing direct contact between the two shells.

[0028] In addition, the arrangement of the two shells in a common volume of the aircraft fuselage section (i.e., the fuselage subsection defined between the first end portion of the first tank and the second end portion of the second tank) provides a compact construction layout that allows optimization of the following volume of the aircraft fuselage section: this volume is dedicated to accommodating the first shell and the second shell that are configured to cover and protect the elements, wherein the elements are responsible for routing and delivering the fuel from the tanks and routing and delivering the fuel to the tanks.

[0029] Advantageously, the length required for the holding tank and the shell of the aircraft fuselage section and the overall fuselage length of the aircraft comprising the aircraft fuselage section are reduced.

[0030] With respect to the material used to manufacture the tank, in an embodiment, at least one of the first tank or the second tank is made of a fiber reinforced polymer ("FRP") material (also referred to as a "composite material").

[0031] Advantageously, the use of composite materials for the manufacture of the tank offers the advantages of composite materials in terms of material properties, weight reduction, material costs, production and industrialisation characteristics.

[0032] In an embodiment, at least one of the first tank or the second tank is metallic.

[0033] According to the invention, the housing is offset at least according to any direction defined in a plane perpendicular to the longitudinal direction.

[0034] In an embodiment, the first housing is further spaced apart from the second housing according to a longitudinal direction.

[0035] In this embodiment, the front-most portion of the second housing is arranged rearwardly relative to the rear-most portion of the first housing.

[0036] In another embodiment, the first shell and the second shell are arranged such that at least one plane perpendicular to the longitudinal direction intersects the two shells.

[0037] In this embodiment, the first shell and the second shell overlap (ie, occupy the same position) along at least a portion of the longitudinal direction. However, since the first shell and the second shell are separated along a direction perpendicular to the longitudinal direction, there is no direct contact between the two shells.

[0038] Once the aircraft fuselage segment is realized as part of an aircraft, the longitudinal direction of the aircraft fuselage segment corresponds to the longitudinal axis of the aircraft, and the vertical plane is the plane defined by the pitch axis and the yaw axis of the aircraft (i.e. the horizontal axis and the vertical axis when considering straight cruising flight).

[0039] In a particular embodiment in which the aircraft fuselage segment is realized as a part of an aircraft, the first shell is spaced apart from the second shell according to a yaw axis of the aircraft.

[0040] In a particular embodiment in which the aircraft fuselage segment is realized as a part of an aircraft, the first shell is spaced apart from the second shell according to a pitch axis of the aircraft.

[0041] In a particular embodiment in which the aircraft fuselage segment is realized as a part of an aircraft, the first shell is spaced apart from the second shell according to a yaw axis and a pitch axis of the aircraft.

[0042] In a specific embodiment, a ratio between a separation distance between the first shell and the second shell in the separation direction and a size of the first shell and the second shell in the separation direction is included in the range of 8% to 10%.

[0043] As defined previously, according to the invention, the shell is offset according to any direction contained in a plane perpendicular to the longitudinal direction. In this sense, the longitudinal direction of the aircraft fuselage segment corresponds to the longitudinal axis of said aircraft once the aircraft fuselage segment is realized as part of the aircraft, and the vertical plane is the plane defined by the pitch axis and the yaw axis of the aircraft (i.e. the horizontal axis and the vertical axis when considering straight cruising flight).

[0044] Therefore, the defined ratio refers to the ratio of the separation distance between the first shell and the second shell along the separation direction to the size or dimension of the shells along the separation direction.

[0045] In a particular embodiment, a dimension of each of the first shell and the second shell in the separation direction is comprised in the range of 40% to 45% of a dimension of the aircraft fuselage segment in the separation direction.

[0046] In a particular embodiment, a separation distance between the first shell and the second shell in the separation direction is comprised in the range of 2% to 10% of a dimension of the aircraft fuselage segment in the separation direction.

[0047] In an embodiment, the first housing is spaced apart from the second tank by a distance according to a longitudinal direction.

[0048] In an embodiment, the second housing is spaced apart from the first tank by a distance according to a longitudinal direction.

[0049] In an embodiment, the coupling between the first shell and the first end portion of the first tank defines an enclosed volume between an inner surface of the first shell and the first end portion.

[0050] In an embodiment, the coupling between the second shell and the second end portion of the second canister defines an enclosed volume between an inner surface of the second shell and the second end portion.

[0051] In an embodiment, the coupling between the first housing and the first end portion of the first tank is configured to ensure the sealing of the enclosed volume defined therein.

[0052] In an embodiment, the coupling between the second housing and the second end portion of the second tank is configured to ensure the sealing of the enclosed volume defined therein.

[0053] In an embodiment, the volume defined between the first and / or second housing and the respective first and / or second end portions accommodates a portion of a conduit routing fuel from and to the tank. In this regard, it will be appreciated that any connecting joints between the housing and the respective end portions and between the housing and any conduit passing through the housing are provided with a fluid tight fit.

[0054] In an embodiment, the first housing and / or the second housing is configured to maintain the enclosed volume defined therein under vacuum conditions.

[0055] Advantageously, the vacuum provided inside the respective housing provides optimal thermal insulation for the piping and / or valve system contained within the first housing and / or the second housing and provides enhanced performance with respect to preventing any failure in the event of a fuel leak and reducing thermal gradient effects between the tank and its external environment.

[0056] In a particular embodiment, the aircraft fuselage segment comprises a frame, and the first shell and / or the second shell are spaced apart from the frame.

[0057] According to this embodiment, the first shell and / or the second shell are dimensioned not to occupy laterally (ie in cross section) the total volume of the fuselage section in which they are located. In this sense, all points of the respective shell should have clearance from the frame of the aircraft fuselage.

[0058] In embodiments where the housing is not aligned with the longitudinal direction of the fuselage section of the aircraft, i.e. the housing is offset and closer to a specific area of ​​the rack, the volume dedicated to accommodating the tank and its corresponding housing can be optimized by a side-by-side configuration or an over-under configuration, but maintaining a clearance of the corresponding housing relative to the nearest area of ​​the rack. This clearance relative to the nearest area of ​​the rack allows enhancing operational safety conditions by preventing direct contact between the corresponding housing and the rack.

[0059] In an embodiment, the tank has a solid of revolution geometry.

[0060] In an embodiment, the first shell and / or the second shell is spaced apart from a nearest portion of the frame by a distance greater than or equal to about 4% of a dimension of the aircraft fuselage segment in the separation direction.

[0061] In certain embodiments, the first canister includes a central portion having a generally cylindrical geometry.

[0062] In certain embodiments, the second canister includes a central portion having a generally cylindrical geometry.

[0063] In a particular embodiment, the first canister includes a central portion having a generally oval geometry.

[0064] In a particular embodiment, the second canister includes a central portion having a generally oval geometry.

[0065] In a particular embodiment, the first canister includes a central portion having a generally frusto-conical geometry.

[0066] In a particular embodiment, the second canister includes a central portion having a generally frusto-conical geometry.

[0067] In a particular embodiment, the aircraft fuselage section comprises a tail cone, and the second can comprises a central portion having a generally frustoconical geometry and is arranged at the tapered section of the tail cone such that the lateral areas of both the second can and the tapered section of the tail cone decrease in the longitudinal direction.

[0068] The fuselage of an aircraft is generally divided into three main components: a tapered nose section housing at least a portion of a cockpit from which the crew controls the operation of the aircraft, a generally tubular section housing the passenger cabin, and a tapered tail cone. The tail cone of an aircraft plays a vital role in the structure and function of the aircraft due to its location.

[0069] The tail cone is defined between the end of the tubular section of the fuselage intended to house the payload and the aft end of the fuselage and therefore represents a smooth transition from a section with substantially constant diameter to a tapering section, that is to say having at least one inclined surface.

[0070] Taking the above into account, according to this embodiment, the second tank is housed in the tail cone of the aircraft fuselage section and has a central portion with a substantially frustoconical geometry, which allows the second tank to adapt to a geometry that gradually narrows toward the rearmost part of the aircraft in the longitudinal direction, thereby optimizing the volume available for storing fuel and allowing the second tank to maintain clearance relative to the tapered frame of the tail cone.

[0071] In an embodiment, the first tank and the second tank are arranged in such a way that the longitudinal axes of their respective substantially cylindrical and / or substantially frustoconical central portions are aligned and parallel to the longitudinal direction of the aircraft fuselage section.

[0072] In an embodiment, the first end portion of the first tank is provided with a dome-shaped geometry.

[0073] In an embodiment, the second end portion of the second tank is provided with a dome-shaped geometry.

[0074] A dome is a structural element shaped like a circular vault and usually has a circular base. A dome is a surface of revolution. These surfaces are produced by rotating a meridian curve about an axis. A meridian curve is considered to be half of the curve formed by a cross section through the center of the dome.

[0075] In an embodiment, the dome-shaped geometry of the first end portion and / or the second end portion is the geometry of a spherical cap.

[0076] In an embodiment, the first end portion and / or the second end portion is arranged to have an annular geometry.

[0077] In a particular embodiment, the first housing is arranged at the apex of the dome-shaped first end portion of the first tank.

[0078] In a particular embodiment, the second housing is arranged at the apex of the dome-shaped second end portion of the second tank.

[0079] It should be understood that the vertex (also referred to as the "pole") of the dome-shaped end portion should correspond to the point of the dome shape that is farthest from the circular base of the dome-shaped end portion. In particular, the vertex generally corresponds to the intersection of the dome-shaped structure and the axis about which the meridian curve rotates to produce the dome geometry.

[0080] The apex of the dome-shaped structure is a point of high stiffness relative to other structural points of the dome-shaped structure. In this sense, the apex of the dome-shaped end portion represents the best location for arranging the piping and valve system that routes the fuel to and from the tank.

[0081] In this respect, according to embodiments in which the first tank and / or the second tank comprises a conduit or valve system arranged at the apex of the dome-shaped end portion, the respective first housing and / or the second housing is preferably also arranged at the respective apex.

[0082] In a second inventive aspect, the invention provides an aircraft comprising an aircraft fuselage segment according to any embodiment of the first inventive aspect.

[0083] In a particular embodiment, the aircraft fuselage section is an unpressurized rear section of the aircraft.

[0084] All features described in this specification (including claims, description and drawings) and / or all steps of the methods may be combined in any combination, except combinations of mutually exclusive features and / or steps. BRIEF DESCRIPTION OF THE DRAWINGS

[0085] These and other features and advantages of the present invention will be clearly understood in view of the detailed description of the present invention which will become apparent from the preferred embodiments of the present invention, which are given by way of example only and not limited thereto, with reference to the accompanying drawings.

[0086] Figure 1 : The figure shows a schematic diagram of a side cross-sectional view of an aircraft fuselage section according to an embodiment of the invention.

[0087] Figure 2 : The figure shows a schematic diagram of a cross-sectional top view of an aircraft fuselage section according to an embodiment of the invention.

[0088] Figure 3 : The figure shows a schematic diagram of an aircraft including an aircraft fuselage section according to an embodiment of the invention. DETAILED DESCRIPTION

[0089] Having outlined the objects of the present invention, specific non-limiting embodiments will be described below.

[0090] Figure 1 A schematic diagram of a side cross-sectional view of an aircraft fuselage segment 10 according to an embodiment of the invention is shown.

[0091] More specifically, the aircraft fuselage section 10 shown is an unstressed fuselage section of an aircraft 20, which also includes the tail cone of the aircraft 20, and which extends along a longitudinal direction X (indicated by the dashed line X). Regarding said longitudinal direction, although only a part of the aircraft 20 is shown, it should be understood that the positive direction of the longitudinal axis X is considered to be from the tail cone of the aircraft 20 towards the cockpit. In this sense, the tail cone is regarded as the rearmost part of the aircraft fuselage section 10. On the other hand, a cross-section of the aircraft fuselage section 10 (i.e. perpendicular to the longitudinal axis X) defines a plane defined by the Y-axis and the Z-axis shown with corresponding dashed lines. As shown Figure 1 As shown, the Z axis (i.e., the vertical direction of the aircraft, perpendicular to the longitudinal axis X) corresponds to the yaw axis. The Y axis (i.e., the horizontal direction of the aircraft, perpendicular to the longitudinal axis X) is shown in the figure which will be described below. Figure 2 and corresponds to the pitch axis.

[0092] like Figure 1 As can be seen in FIG. 1 , the aircraft fuselage section 10 comprises a first fuel storage tank 11 and a second fuel storage tank 12 which are arranged in a tail tandem configuration such that the second tank 12 is arranged continuously according to a longitudinal direction X relative to the first tank 11 .

[0093] Both the first tank 11 and the second tank 12 are configured to contain fuel therein. In an embodiment, both tanks 11, 12 are cryogenic tanks and are configured to contain liquid hydrogen.

[0094] As can be seen, the first tank 11 comprises a central portion of generally cylindrical geometry. Two respective end portions are arranged at both sides of said central portion according to the longitudinal axis X, said end portions being arranged in a dome-shaped geometry. More specifically, with reference to the last end portion of the first tank 11, this last end portion is referred to as the first end portion 11.1 of the first tank 11. As can be seen, said first end portion 11.1 is oriented rearwards, i.e. towards the position of the second tank 12.

[0095] The second tank 12 comprises a central portion of generally truncated cone-shaped geometry. Two respective end portions are arranged at both sides of said central portion according to the longitudinal axis X, said end portions being arranged in a dome-shaped geometry. More specifically, with reference to the forwardmost end portion of the second tank 12, this forwardmost end portion is referred to as the second end portion 12.1 of the second tank 12. As can be seen, said second end portion 12.1 is oriented forwards, i.e. towards the position of the first tank 11.

[0096] Furthermore, as can be seen, in this embodiment, the tail cone of the aircraft fuselage segment 10 of the aircraft 20 shown is as shown. Figure 1 The illustrated tapered geometry has a bottom surface that slopes upward, which results in the fuselage cross section decreasing in the longitudinal direction towards the rearward portion of the aircraft 20 .

[0097] In this sense, Figure 1 In the embodiment shown in FIG. 1 , the central portion of the second tank 12 is also provided with a lowermost surface inclined upward (according to Figure 1 ) to fit the tapering volume of the tail cone, thereby optimizing the volume available for storing fuel.

[0098] The end portion 11.1 of the first tank 11 and the second end portion 12.1 of the second tank 12 are arranged to be oriented in opposite directions. In this sense, as can be seen, a partition is provided between the first tank 11 and the second tank 12 along the longitudinal axis X. More specifically, a certain volume of the aircraft fuselage segment 10 is defined as a fuselage sub-segment 13 of the aircraft fuselage segment 10, said sub-segment 13 of the aircraft fuselage segment 10 being defined between the first end portion 11.1 of the first tank 11 and the second end portion 12.1 of the second tank 12. For illustration purposes, in Figure 1 and Figure 2 In both, the subsection 13 is shown constrained by two restrictions indicated by dashed lines provided in the first tank 11 and the second tank 12 at the boundaries between the central portion and the respective end portions 11 . 1 , 12 . 1 .

[0099] In addition, a first housing 14 and a second housing 15 are arranged at the first end portion 11.1 of the first tank 11 and the second end portion 12.1 of the second tank 12, respectively. Each housing 14, 15 is configured to accommodate a conduit (not shown), such as a pipe and / or a valve system that is in fluid communication with the interior of the corresponding first tank 11 or second tank 12, and each housing 14, 15 serves as an enclosure that acts as a safety layer to prevent any failure in the event of a fuel leak and minimize the thermal gradient effect between the corresponding tank 11, 12 and its external environment.

[0100] exist Figure 1 In the embodiment shown in FIG. 1 , the first housing 14 and the second housing 15 are configured to maintain the conduits contained in the first housing 14 and the second housing 15 under vacuum conditions. More specifically, the connection between the first housing 14 and the first end portion 11.1 of the first tank 11 defines a closed volume between the inner surface of the first housing 14 and the first end portion 11.1. Successively, the connection between the second housing 15 and the second end portion 12.1 of the second tank 12 defines a closed volume between the inner surface of the second housing 15 and the second end portion 12.1.

[0101] In an embodiment, the coupling between the first housing 14 and the first end portion 11 . 1 of the first tank 11 ensures the sealing of the closed volume defined therein.

[0102] Successively, the coupling between the second housing 15 and the second end portion 12 . 1 of the second tank 12 ensures the tightness of the closed volume defined therein.

[0103] In this regard, in order to maintain the enclosed volume contained therein under vacuum conditions, it should be understood that any connecting joints between the shells 14, 15 and the corresponding end portions 11.1, 12.1 of the tanks 11, 12, as well as any connecting joints between the shells 14, 15 and any pipes passing through the shells 14, 15 are provided with fluid-tight fittings.

[0104] With regard to the arrangement of the first shell 14 and the second shell 15 relative to each other, it can be seen that the first shell 14 extends from the first end portion 11.1 of the first tank 11 into the fuselage subsection 13, and the second shell 15 extends from the second end portion 12.1 of the second tank 12 into the fuselage subsection 13. In this sense, Figure 1 Two shells 14, 15 are shown, which are schematically depicted as corresponding squares. As can be seen, the first shell 14 and the second shell 15 are spaced apart from each other according to a direction perpendicular to the longitudinal direction X and more specifically according to the Z axis. In this embodiment, as can be seen, the shells 14, 15 are arranged according to an up-and-down layout. More specifically, the first shell 14 is positioned in an upper position relative to the second shell 15. As shown, the first shell 14 is separated from the second tank 12, and more specifically from the second end portion 12.1 according to the longitudinal direction X. Sequentially, the second shell 15 is separated from the first end portion 11.1 of the first tank 11 by a distance according to the longitudinal direction X. In addition, in this embodiment, there is also a separation distance according to the longitudinal direction X between the first shell 14 and the second shell 15. That is, the frontmost part of the second shell 15 is arranged at the back according to the longitudinal direction X relative to the rearmost part of the first shell 14.

[0105] Figure 2 A schematic diagram of a cross-sectional top plan view of an aircraft fuselage segment 10 according to an embodiment of the invention is shown.

[0106] Figure 2 The aircraft fuselage segment 10 shown in FIG. Figure 1 In particular, the aircraft fuselage section 10 shown is an unstressed fuselage section of an aircraft 20 , the aircraft fuselage section 10 shown also comprising a tail cone of the aircraft 20 .

[0107] It can be seen that the first fuel storage tank 11 and the second fuel storage tank 12 are arranged in a tail-in-tank configuration such that the second tank 12 is arranged continuously according to the longitudinal direction X relative to the first tank 11 .

[0108] As regards the geometrical references used to describe the relative positions of the elements of the fuselage section 10, Figure 1 As in the example, it should be understood that the positive direction of the longitudinal axis X is considered to be from the tail cone towards the cockpit of the aircraft 20. The Y axis (ie the horizontal direction of the aircraft, perpendicular to the longitudinal axis X) corresponds to the pitch axis.

[0109] The second tank 12 comprises a central portion having a generally frustoconical geometry, and the tail cone of the aircraft 20 comprises a tapered geometry, resulting in a reduction in the fuselage cross section in the longitudinal direction towards the rearmost portion of the aircraft 20. Figure 1 The arrangement shown is similar, with the second tank 12 having a frusto-conical central portion adapted to fit within the tapering volume of the tail cone, thereby optimizing the volume available for storing fuel.

[0110] With regard to the arrangement of the first shell 14 and the second shell 15, the first shell 14 is spaced apart from the second shell 15 according to a direction perpendicular to the longitudinal direction X and more specifically according to the Y axis shown. In this sense, Figure 2 Two housings 14, 15 are shown schematically depicted as corresponding squares. Figure 1 The layout shown is similar, and it can be seen that the first shell 14 extends from the first end portion 11.1 of the first tank 11 into the fuselage subsection 13 defined between the first end portion 11.1 of the first tank 11 and the second end portion 12.1 of the second tank 12, and the second shell 15 extends from the second end portion 12.1 of the second tank 12 into said fuselage subsection 13. Furthermore, the first shell 14 is spaced apart from the second tank 12, and more specifically from the second end portion 12.1 by a distance according to the longitudinal direction X. Consecutively, the second shell 15 is spaced apart from the first end portion 11.1 of the first tank 11 by a distance according to the longitudinal direction X.

[0111] Finally, as can be seen, there is also a gap between each of the shells 14 , 15 and the portion of the fuselage frame closest to each shell 14 , 15 .

[0112] at the same time, Figure 1 A schematic diagram of the layout of the housings 14, 15 is shown, wherein the two housings 14, 15 are offset according to:

[0113] - a direction contained in a plane perpendicular to the longitudinal direction and more specifically according to the direction of the yaw axis Z, and

[0114] - a longitudinal direction X, that is to say, in which the frontmost part of the second housing is arranged behind the rearmost part of the first housing,

[0115] exist Figure 2 In the embodiment, the first shell 14 and the second shell 15 are arranged so that at least one plane perpendicular to the longitudinal direction X intersects the two shells, that is, Figure 2 , the first shell 14 and the second shell 15 overlap at least a portion along the longitudinal direction X (ie, occupy the same position).

[0116] In addition, although Figure 1 A schematic diagram of an upper and lower arrangement of the shells 14, 15 according to the main directions of the aircraft 20 is shown, i.e. the upper and lower arrangement has a separation distance between the shells 14, 15 along the yaw axis Z, Figure 2 An alternative arrangement with the housings 14 , 15 spaced apart in a side-by-side configuration, ie with no separation between the housings relative to the yaw axis Z, but with a separation according to the pitch axis Y, is shown.

[0117] Both the over-under and the side-by-side arrangements offer the advantage of allowing a reduction in the length of the aircraft fuselage section 10 intended to store fuel, compared to an aircraft in which the elements responsible for routing the fuel from and into the tanks are not arranged in the same subsection of the aircraft fuselage section.

[0118] Finally, a configuration of a relative arrangement between the housings 14 , 15 with a combined offset in the yaw axis Z and in the pitch axis Y is also possible and has the same advantages.

[0119] Figure 3 An embodiment of an aircraft 20 is shown, which comprises an aircraft fuselage segment 10 according to an embodiment of the invention.

Claims

1. An aircraft fuselage section (10) extending along a longitudinal direction (X), wherein: The fuselage section (10) comprises a first fuel storage tank (11) and a second fuel storage tank (12), the first fuel storage tank (11) and the second fuel storage tank (12) being arranged in a tail tandem configuration such that the second tank (12) is arranged continuously relative to the first tank (11) according to the longitudinal direction (X); wherein the first tank (11) comprises a first end portion (11.1) oriented toward the second tank (12), and the second tank (12) comprises a second end portion (12.1) oriented toward the first tank (11), such that a body section (13) is defined between the first end portion (11.1) of the first tank (11) and the second end portion (12.1) of the second tank (12); Wherein, the aircraft fuselage section (10) further comprises: a first housing (14) arranged at the first end portion (11.1) of the first tank (11), the first housing (14) being configured to accommodate a conduit in fluid communication with the interior of the first tank (11), and a second housing (15) arranged at the second end portion (12.1) of the second tank (12), the second housing (15) being configured to accommodate a conduit in fluid communication with the interior of the second tank (12); And among them, The first shell (14) extends from the first end portion (11.1) of the first tank (11) into the fuselage section (13), The second shell (15) extends from the second end portion (12.1) of the second tank (12) into the fuselage section (13), and The first housing (14) is spaced apart from the second housing (15) according to a partition direction contained in a plane perpendicular to the longitudinal direction (X).

2. The aircraft fuselage segment (10) according to claim 1, wherein: The first shell (14) and the second shell (15) are arranged such that at least one plane perpendicular to the longitudinal direction (X) intersects the two shells (14, 15).

3. An aircraft fuselage segment (10) according to any one of the preceding claims, wherein: A ratio between a separation distance between the first shell (14) and the second shell (15) in the separation direction and a size of the first shell (14) and the second shell (15) in the separation direction is within a range of 8% to 10%.

4. An aircraft fuselage segment (10) according to any one of the preceding claims, wherein: The dimension of each of the first shell (14) and the second shell (15) in the separation direction is comprised in the range of 40% to 45% of the dimension of the aircraft fuselage segment (10) in the separation direction; and / or The separation distance between the first shell (14) and the second shell (15) in the separation direction is comprised in the range of 2% to 10% of a dimension of the aircraft fuselage segment (10) in the separation direction of the aircraft fuselage segment (10).

5. Aircraft fuselage segment (10) according to any one of the preceding claims, wherein: The first housing (14) and / or the second housing (15) are configured to maintain the corresponding enclosed volume defined therein under vacuum conditions.

6. Aircraft fuselage segment (10) according to any one of the preceding claims, wherein: The aircraft fuselage segment (10) comprises a frame, and wherein the first shell (14) and / or the second shell (15) are spaced apart from the frame.

7. The aircraft fuselage segment (10) according to claim 6, wherein: The first shell (14) and / or the second shell (15) are spaced apart from the nearest part of the frame by a distance greater than or equal to about 4% of a dimension of the aircraft fuselage segment (10) in the separation direction.

8. Aircraft fuselage segment (10) according to any one of the preceding claims, wherein: The first tank (11) and / or the second tank (12) comprises a central portion having a generally cylindrical geometry.

9. Aircraft fuselage segment (10) according to any one of the preceding claims, wherein: The first tank (11) and / or the second tank (12) comprises a central portion having a generally frustoconical geometry.

10. The aircraft fuselage section (10) according to claim 9, further comprising a tail cone, wherein: The second tank (12) includes a central portion having a generally frustoconical geometry and is arranged at a tapered section of the tail cone such that the lateral areas of both the second tank (12) and the tapered section of the tail cone decrease along the longitudinal direction.

11. Aircraft fuselage segment (10) according to any one of claims 8 to 10, wherein: The first tank (11) and the second tank (12) are arranged in such a way that the longitudinal axes of their respective substantially cylindrical and / or substantially frustoconical central portions are aligned and parallel to the longitudinal direction of the aircraft fuselage section (10).

12. Aircraft fuselage segment (10) according to any one of the preceding claims, wherein: The first end portion (11.1) of the first tank (11) and / or the second end portion (12.1) of the second tank (12) are provided with a dome-shaped geometry.

13. Aircraft fuselage segment (10) according to the preceding claim, wherein: The first shell (14) and / or the second shell (15) are arranged at the apex of the respective dome-shaped end portions of the first tank (11) and / or the second tank (12).

14. An aircraft (20) comprising an aircraft fuselage segment (10) according to any one of the preceding claims.

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