Aircraft pylon equipped with a guidance system for mounting or dismounting a tank and method of mounting/dismounting said tank

1 . An aircraft pylon comprising:

a box-section primary structure including at least one lateral wall which delimits an interior zone and an exterior zone and includes at least one through-hole enabling the interior and exterior zones to communicate,

at least one tank occupying in the interior zone of the primary structure a mounted position offset in a longitudinal direction parallel to the lateral wall relative to the through-hole,

at least one attachment system demountably connecting the tank and the primary structure,

wherein the aircraft pylon is equipped, at least when mounting or demounting the tank, with at least one guide system configured to move the tank from its mounted position toward the through-hole, said guide system including at least one guide pin fastened to the tank, one guide rail positioned above the tank that extends in the longitudinal direction between first and second ends, and a connecting system connecting the guide rail and the primary structure, the first end of the guide rail being situated in a vicinity of or in line with the through-hole, the second end being offset from the through-hole, the guide pin and the guide rail being configured to cooperate with each other so that the tank is supported by the guide rail and able to slide along the guide rail.

2 . The aircraft pylon as claimed in claim 1 , wherein the connecting system is configured to allow at least the second end of the guide rail to be moved in a vertical direction.

3 . The aircraft pylon as claimed in claim 2 , wherein the connecting system comprises:

a pivoting first connection situated in a vicinity of the first end of the guide rail, connecting the guide rail to the primary structure and including a horizontal pivot pin perpendicular to the longitudinal direction,

an elastically deformable second connection offset toward the second end of the guide rail relative to its first end and connecting the guide rail and the primary structure.

4 . The aircraft pylon as claimed in claim 3 , wherein the second connection comprises a leaf spring that has a first end connected to the guide rail and a second end offset in the longitudinal direction relative to the first end and connected to the primary structure.

5 . The aircraft pylon as claimed in claim 4 , wherein the first end of the leaf spring is oriented toward the first end of the guide rail and the second end of the leaf spring is oriented toward the second end of the guide rail, the first end of the leaf spring being closer to the first end of the guide rail than its second end.

6 . The aircraft pylon as claimed in claim 5 ,

wherein the first end of the leaf spring is pressed against the guide rail and is connected to the guide rail by at least one connecting element, and

wherein the second connection comprises at least one hook fastened to the second end of the leaf spring configured to be hooked onto the primary structure.

7 . The aircraft pylon as claimed in claim 6 ,

wherein the primary structure of the aircraft pylon comprises transverse frames, one of the transverse frames having a core positioned in a transverse plane and a rim projecting relative to the core and oriented in a direction away from the through-hole, and

wherein the hook has a Z-shape profile and comprises a flange oriented in the direction of the through-hole configured to cooperate with the rim of the transverse frame.

8 . The aircraft pylon as claimed in claim 7 , wherein the second connection comprises at least one system for keeping the hook hooked onto the transverse frame.

9 . The aircraft pylon as claimed in claim 1 , wherein the guide pin has a revolution axis and comprises a head and a foot connecting the head to the tank, the head having a larger section than the foot.

10 . The aircraft pylon as claimed in claim 9 , wherein the tank has a revolution axis, the revolution axes of the guide pin and the tank coinciding.

11 . The aircraft pylon as claimed in claim 1 , wherein the guide rail comprises:

a body that has a lower face oriented toward the tank, a first end face situated at a level of the first end of the guide rail and a second end face situated at a level of the second end of the guide rail,

a groove provided in the body opening onto the lower face of the body that has a T-shape cross section configured to accommodate the guide pin.

12 . The aircraft pylon as claimed in claim 11 , wherein the groove opens onto the first and second end faces of the body.

13 . The aircraft pylon as claimed in claim 12 , wherein the first end of the guide rail being situated in a vicinity of or in line with the through-hole, the groove has an opening section extending as far as the first end face at a level of which the groove is flared in a direction of the first end face.

14 . A method of demounting a tank positioned in an aircraft pylon as claimed in claim 1 , wherein the demounting method comprises:

unfastening the tank from the primary structure of the pylon,

mounting the guide rail to cause the guide pin to cooperate with the guide rail and to connect the guide rail to the primary structure,

sliding the tank along the guide rail in a direction of the first end of the latter, the tank being suspended from the guide rail,

unfastening the guide pin and the guide rail,

manipulating the tank to cause the tank to pass through the through-hole.

15 . The method as claimed in claim 14 , wherein the method comprises lifting and pivoting the tank before sliding the tank along the guide rail.

16 . A method of mounting a tank positioned in an aircraft pylon as claimed in claim 1 , wherein the mounting method comprises:

manipulating the tank to cause the tank to pass through the through-hole to position the tank in the interior zone of the primary structure,

suspending the tank from the guide rail by causing the guide pin and the guide rail to cooperate,

sliding the tank along the guide rail in a direction of the second end of the latter,

positioning the tank relative to the attachment system,

demounting the guide rail,

fastening the tank to the primary structure of the pylon.