Abstract: An aircraft body or fuselage is divided by a main deck (3) to form an upper deck and a lower deck. The lower deck has its own floor (5). A connecting device or several such devices, for example stairs and/or elevators, interconnect the upper deck with the lower deck in positions to facilitate central access to a plurality of lower deck facilities. Supply facilities and sanitary facilities are arranged on the lower deck to provide additional seating space on the upper deck. The lower deck may also hold resting areas, such as a lounge that may be equipped with beds, such as convertible beds. A food distribution station is arranged on the upper deck in vertical alignment with a galley on the lower deck. All the facilities of a group of facilities on the lower deck are centrally accessible.