Anterior Zone Of An Aircraft Having A Simplified Structure

Abstract

An anterior zone of an aircraft, having a fuselage with frames, includes a cockpit, arranged partly above a front landing gear compartment, and a service area. The floor includes: a rear main crossbeam which extends in the plane of a frame situated in the service area and which is fixed to said frame, a port main spar and a starboard main spar, the rear ends of which are fixed to the rear main crossbeam, one or more secondary crossbeams, fixed to the port and starboard main spars, and one or more auxiliary spars. The number of crossbeam/frame attachments is reduced. The dimensioning of the principal beams of the floor is optimised; the result thereof is a weight saving.

Claims

1. An anterior zone of an aircraft comprising a fuselage with frames, the anterior zone accommodating a cockpit, arranged partly above a front landing gear compartment, and a service area, the anterior zone having a floor comprising crossbeams, spars and one or more floor panels, wherein the floor comprises: a rear main crossbeam extending in the plane of a frame situated in the service area, wherein the rear main crossbeam is fixed to said frame; a port main spar and a starboard main spar, wherein each of the main spars has a rear end fixed to the rear main crossbeam; one or more secondary crossbeams, fixed to the port and starboard main spars, wherein the one or more secondary crossbeams are not fixed to any frame, and are borne by the main spars, wherein the floor does not comprise any crossbeam fixed to a frame in the cockpit; and one or more auxiliary spars.

2. The anterior zone of an aircraft according to claim 1, wherein each of the port and starboard main spars has a front end fixed to a structural element of the front landing gear compartment.

3. The anterior zone of an aircraft according to claim 2, wherein the structural element of the front landing gear compartment forms part of a horizontal section of roof of the gear compartment.

4. The anterior zone of an aircraft according to claim 1, wherein: the one or more secondary crossbeams extend only from the port main spar to the starboard main spar, and the one or more floor panels cover a surface delimited transversely by the port and starboard main spars such that there remain two lateral bands without crossbeam and floor panel.

5. The anterior zone of an aircraft according to claim 1, further comprising a reinforcing crossbeam fixed to a frame situated in the service area, in front of the rear main crossbeam.

6. The anterior zone of an aircraft according to claim 1, further comprising a port reinforcing spar and a starboard reinforcing spar, each of the port reinforcing spar and the starboard reinforcing spar having a rear end fixed to the rear main crossbeam.

7. The anterior zone of an aircraft according to claim 6, wherein each of the port and starboard main spars has a front end fixed to a structural element of the front landing gear compartment, and wherein each of the port reinforcing spar and the starboard reinforcing spar has a front end fixed to the structural element of the front landing gear compartment.

8. The anterior zone of an aircraft according to claim 1, wherein the auxiliary spars do not extend over all of the longitudinal dimension of the anterior zone.

9. An aircraft comprising an anterior zone according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1 is a perspective schematic view from above and behind an anterior zone floor according to an embodiment of the invention, in which the floor panels have not been represented.

[0028] FIG. 2 is a perspective schematic view from above and from the front of the floor of FIG. 1 mounted in an aircraft fuselage and with its floor panels.

[0029] FIG. 3 is a profile schematic view of an aircraft equipped with an advanced front gear compartment (qualified thus because of its position) and of a floor according to an embodiment of the invention.

DETAILED DESCRIPTION

[0030] FIG. 1 represents the skeleton of a floor of an anterior zone of a passenger transport aircraft, which anterior zone comprises a part 30 receiving a cockpit and a part 32 receiving a service area with galley and toilets (not represented).

[0031] Under this floor, there are, from the front to the rear of the aircraft, a front landing gear compartment (simply called front gear compartment hereinbelow) and a technical hold which extends under the cockpit and under the service area. The technical hold is open in the upper part and is pressurised like the cockpit.

[0032] There are mainly two types of front gear compartment: so-called conventional front gear compartments, which extend essentially under the cockpit, or even only in the central or rear part of the cockpit, such that there is a pressurised space between the front gear compartment and the sealed nose cone of the aircraft; and so-called advanced front gear compartments such as that illustrated in FIG. 3, which extend to the sealed nose cone 33 of the aircraft. The front gear compartment 31 whose roof can be seen in FIGS. 1 and 2 is an advanced compartment. Aspects of the invention apply to the aircraft provided with an advanced gear compartment and for the aircraft provided with a conventional gear compartment. However, it is more advantageous in the case of an advanced compartment for which the absence of free space (pressurised) between the sealed nose cone and the gear compartment complicates the running of the systems to the cockpit.

[0033] The roof of the (advanced) front gear compartment that can be seen in FIG. 1, comprises a horizontal section 38 and an inclined section 39.

[0034] The floor of the anterior zone illustrated in FIGS. 1 and 2 comprises a rear main crossbeam 2 fixed onto and borne by a frame 20 of the fuselage of the aircraft which is situated in the service area. The fixing of the rear main crossbeam 2 onto the frame 20 can be done using ties 36 as in the known prior floors.

[0035] The anterior zone floor according to an embodiment of the invention illustrated in FIGS. 1 and 2 also comprises a port main spar 4 and a starboard main spar 6 whose rear ends are fixed onto and borne by the rear main crossbeam 2, and whose front ends are fixed onto and borne by a structural element 34 forming part of the horizontal section of roof 38 of the front gear compartment.

[0036] It should be noted that the roof of the front gear compartment is dimensioned so as to be able to withstand a significant pressure difference since it is exposed on one side (above the compartment) to the pressure prevailing in the cockpit and on the other side to the pressure outside the aircraft. The roof of the compartment therefore comprises structural elements capable of taking up significant loads, such as the beam 34 in the rear part of the horizontal section of roof 38. An aspect of the invention here advantageously exploits this feature.

[0037] The anterior zone floor according to an embodiment of the invention illustrated in FIGS. 1 and 2 also comprises a reinforcing crossbeam 8, and a port reinforcing spar 10 and a starboard reinforcing spar 12.

[0038] The reinforcing crossbeam 8 is fixed to a frame 22 of the fuselage. The frame 22 is the one which precedes the frame 20, that is to say the one which is situated immediately in front of the frame 20 to which the rear main crossbeam 2 is fixed. The reinforcing spars 10 and 12 are fixed in the same way as the main spars 4 and 6, that is to say that they are fixed to the rear main crossbeam 2 by their rear end and to the structural element 34 of the front gear compartment by their front end.

[0039] It should be noted that the port 4 and starboard 6 main spars, and the reinforcing spars 10 and 12, are also borne by the reinforcing crossbeam 8.

[0040] The anterior zone floor according to an embodiment of the invention illustrated in FIGS. 1 and 2 also comprises two secondary crossbeams 14, 15 which extend only from the port main spar 4 to the starboard main spar 6. These secondary crossbeams are fixed onto and borne by the main spars 4 and 6 and the reinforcing spars 10 and 12. The floor could comprise other secondary crossbeams or, on the contrary, a single secondary crossbeam.

[0041] The anterior zone floor according to an embodiment of the invention illustrated in FIGS. 1 and 2 also comprises auxiliary spars 16, 17, 18, 19. The auxiliary spars 16, 17 extend from the reinforcing crossbeam 8 to the secondary crossbeam 14, to which they are fixed. The auxiliary spars 18, 19 extend from the secondary crossbeam 14 to the structural element 34 of the front gear compartment, to which they are fixed.

[0042] The network of the crossbeams and auxiliary spars is not limited to that illustrated in the attached figures. The distribution of the crossbeams and auxiliary spars can vary and the positioning of the various auxiliary spars and secondary crossbeams should be determined as a function of the mechanical loads that the floor must withstand. As an example, the pilot and copilot seats having a base, it is preferable to position the intersections of the crossbeams and auxiliary spars in line with the fixings of these bases for reasons of structural efficiency. Beyond this logic, crossbeams and/or auxiliary spars can be added if the grid size is too great to ensure the rigidity of the walking zones of the floor for example.

[0043] The anterior zone floor according to an embodiment of the invention finally comprises floor panels. As a variant, a single floor panel 40 is provided covering all the crew walking surface, this service comprising all of the service area and only a part of the cockpit. In the example illustrated, this (single) panel is holed, holes 42 being provided in places to reduce the weight of the floor while ensuring the resistance to the global mechanical loads that the floor is subjected to. The holes can be plugged by lighter plates in order to ensure placement of the floor covering (of fitted carpet type) and to withstand the crew walking load.

[0044] As can be seen in FIG. 2, the frames 24, 26, 28, which precede the frame 22 to which the reinforcing crossbeam 8 is fixed, do not bear any crossbeam. No crossbeam encumbers the space 44 (lateral band) extending transversely between the port main spar 4 and the fuselage, as for the space 46 (lateral band) extending transversely between the starboard main spar 6 and the fuselage. These two lateral bands are not crew walking zones but zones receiving mainly navigation tools or other equipment, even lost zones not used in the cockpit floor. As a consequence of this, the lateral bands 44 and 46 can advantageously be without floor panel (as illustrated in FIG. 2). They are therefore without any structural floor element (neither crossbeam nor floor panel). This means that no obstacle opposes the vertical running of the systems between the cockpit and the technical hold in said lateral bands 44 and 46.

[0045] The invention extends to any variant accessible to the person skilled in the art, that is to say following within the scope delimited by the attached claims.

[0046] 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. 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.