Aircraft structure assembly

An aircraft structure assembly (10) comprises a surface element (12) having a core (20) and an outer layer (22). A first surface (30) of the surface element (12) is conceived with respect to a, through the core (20) of the surface element (12) extending central area (Z) of the surface element (12) at least partially convexly curved. One of the first surface (30) opposite second surface (32) of the surface element (12), however, is at least partially drawn parallel to that through the core (20) of the surface element (12) extending central area (Z) of the surface element (12) aligned , The surface element (12) is in the form of a floor panel of a floor system (14). The first or the second surface (30, 32) of the surface element (12) is adapted to form, in the assembled state in a plane of the aircraft structure assembly (10) has a walk-floor surface of the floor system (14).