Pivoting coupling system for a large dihedral empennage to the tail fuselage of an aircraft

A pivoting coupling system of a large dihedral empennage for coupling the empennage to a tail fuselage of an aircraft, the empennage including a right lateral box and a left lateral box forming a large dihedral angle in the tail fuselage of the aircraft, said pivoting coupling system comprising:

• a horizontal central box joining the lateral boxes, and including a rear spar;
• and
• a plurality of linked rotary fittings for horizontally linking the central box to a frame structure of the tail fuselage of the aircraft, said plurality of linked rotary fittings enabling the empennage to rotate vertically about a horizontal linkage shaft between a negative maximum angle of incidence and a positive maximum angle of incidence in response to actuation of an actuator means connected to the fuselage and to a structural element of the fuselage of the aircraft;
• wherein the frame structure comprises a closed frame, and
• said plurality of linked rotary fittings comprises
• a first linked fitting provided in the proximity of the right box, said first linked fitting comprising a first rotary fitting provided in the frame structure and linked by a first bolt to a complementary first rotary fitting provided in said rear spar of the empennage,
• a second linked fitting provided in the proximity of the left box, said second linked fitting comprising a second rotary fitting provided in the frame structure linked by a second bolt to a complementary second rotary fitting provided in said rear spar of the empennage, and
• each rotary fitting of said complementary first and second rotary fittings in turn comprising at least one complementary opening aligned with at least one opening in one of the first and second rotary fittings in order to form a space in which the bolt is housed;
• a lateral load linked fitting in order to prevent lateral displacements of the empennage, which is provided in the central box between said first and second linked fittings and which comprises two lateral load fittings provided in the frame structure linked to at least one complementary lateral load fitting which is provided in said rear spar of the empennage, the lateral load fittings being linked together such that they permit the empennage to rotate on the horizontal shaft.