System for opening and closing a landing-gear compartment for an aircraft

1. A system for opening and closing a landing-gear compartment of an aircraft comprising:

a plurality of hatches mounted on a fairing of the aircraft,

the plurality of hatches comprising main hatches with transversal opening and at least one secondary hatch with a longitudinal opening;

said at least one secondary hatch has an outer surface that faces the outside of the aircraft and is flush with a fairing outer surface when in a closed position;

a hinge system comprising:

a mobile part;

a fixed part, said fixed part has a rigid link with the fairing of the aircraft;

said mobile part is linked to the fixed part and to the secondary hatch by rotating links;

a linking element is fixed to a landing gear leg by a rigid link and is connected to the secondary hatch by a rotating link; and

wherein said hinge system is configured to maintain the at least one secondary hatch parallel to the fairing outer surface during opening and in a fully open position.

2. The system according to claim 1 , wherein in said closed position said secondary hatch is placed in the continuity of the fairing of the aircraft.

3. The system according to claim 1 , wherein the secondary hatch is fixed to the fairing of the aircraft by means of the hinge system giving the secondary hatch a motion of vertical translation and a combined motion of rotation and horizontal translation.

4. The system according to claim 3 , wherein the mobile part is comprised of a goose-necked hinge fixed by said rotating links, said rotating links are comprised of a first rotating link to the fairing and by a second rotating link to the secondary hatch.

5. The system according to claim 4 , wherein the second rotating link comprises a plurality of ties distributed on the secondary hatch.

6. The system according to claim 5 , wherein at least one of the ties provides for a rotation of the goose-necked feature and a gradual kinematic locking of the secondary hatch.

7. The system according to claim 3 , wherein the linking element forms a stop for the closing of the main hatches.

8. The system according to claim 1 , wherein the secondary hatch is equipped with a stiffening piece.

9. The system according to claim 8 , wherein least one tie is incorporated into the stiffening piece.

10. The system according to claim 1 , wherein the main hatches comprise two main hatches and the at least one secondary hatch comprises a single secondary hatch.

11. An aircraft comprising a system for opening and closing a landing-gear compartment according to claim 1 .