Fuel line in an aircraft

1. A line segment of a fuel line in an aircraft for connecting at least three lines, comprising:

a wall structure forming a continuous cavity, wherein the wall structure has at least three adapter openings configured to connect the continuous cavity with one line respectively, and wherein the wall structure consists of two half-shells, each half-shell defining a continuous, one-piece structure that includes an inner wall, an outer wall, and a rib that permanently fixes the inner wall to the outer wall, such that an intermediate cavity is formed between the inner wall and the outer wall, the inner wall defining the continuous cavity within which contents of the line segment flow through.

2. The line segment as recited in claim 1 , wherein an adapter flange is respectively arranged at each of the at least three adapter openings,

wherein the inner wall, the outer wall, and the adapter flange are integrally formed;

wherein the adapter flanges have two connector bars configured on a diametrically opposed side of connection faces and stick out in a direction of the walls that are to be connected; and

wherein the inner wall and the outer wall are connected with their facing sides with the facing sides of the two connector bars.

3. The line segment as recited in claim 1 , wherein the line segment is a T-piece having a T-bar and a T-flange, wherein an end of the T-bar has a first connection, and wherein two ends of the T-flange respectively have a second and third connection.

4. The line segment as recited in claim 1 , wherein the two half-shells of the outer wall are mounted at the rib.

5. An aircraft, comprising:

a fuselage;

an aerodynamic lift system;

a propulsion drive system; and

a fuel tank system,

wherein the fuel tank system has at least two refueling cells connected with a line, wherein the line has at least one line segment for connecting at least three lines, the line segment comprising

a wall structure forming a continuous cavity, wherein the wall structure has at least three adapter openings configured to connect the continuous cavity with one line respectively, and wherein the wall structure consists of two half-shells, each half-shell defining a continuous, one-piece structure that includes an inner wall, an outer wall, and a rib that permanently fixes the inner wall to the outer wall, such that an intermediate cavity is formed between the inner wall and the outer wall, the inner wall defining the continuous cavity within which contents of the line segment flow through.

6. The method as recited in claim 5 , wherein

at least the outer wall consists of two half-shells,

an adapter flange is respectively arranged at each of the at least three adapter openings, and

the inner wall, the outer wall, and the adapter flange are integrally formed.

7. A method for the production of a line segment of a fuel line in an aircraft for connecting at least three lines with at least three adapters, the method comprising the steps:

a) configuring a first half-shell of in such a way that an intermediate cavity is formed between a first inner and a first outer wall of the first half-shell to form a wall structure, wherein the inner wall defines a continuous cavity within which contents of the line segment flow through, and wherein the wall structure has at least three adapter openings for connecting the continuous cavity with respectively one line;

b) configuring a second half-shell in such a way that an intermediate cavity is formed between a second inner and a second outer wall of the second half-shell, wherein the intermediate cavity surrounds the continuous cavity;

c) connecting the first half-shell with the second half-shell; and

d) connecting the first and second outer wall with adapter flanges, one of which is provided at each connection opening, wherein the connection is configured such that each of the first and second outer wall is respectively connected with the first and second inner wall via the connection flange, wherein

the first half-shell is a continuous, one-piece structure that includes the first inner wall, the second wall, and a reinforcement rib that permanently fixes the first inner wall to the first outer wall.

8. The method as recited in claim 7 , wherein prior to step d), an adapter flange is located at each adapter opening; and wherein in step d), the adapter flanges are also connected with the first and second inner wall.

9. The method as recited in claim 7 , wherein the first and the second half-shell are produced with an integral wall and are cut into two half-shells by using a cutting process along a joint,

wherein the reinforcement rib and the joint are coordinated with each other in terms of their dimensions, and

wherein the connection in step c) takes place in the section of the joint and whereby the first and the second half-shell are connected with each other via the reinforcement ribs.

10. The method as recited in claim 7 , wherein at least the first inner wall, the first outer wall, and the adapter flanges are integrally formed.