Fuselage arrangement for airplane

An aircraft fuselage elongated along a longitudinal axis of an aircraft that determines a direction toward a front of the aircraft along a direction of motion of the aircraft in flight, comprising:

• a front part with straight cross sections widening relative to the longitudinal axis,
• said front part ending in front with a fuselage nose and being delimited at a rear by a joining cross section similar to a cross section of a rear part, essentially cylindrical of the fuselage,
• said front part comprising a cockpit located above a floorboard between a cockpit bulkhead to the rear and a front wall at the front, wherein lower shapes of a working structure of the front part determine a lower bulge such that each straight cross section of the working structure of the fuselage has a single curvature rounded shape and such that a lower profile of the working structure of the fuselage, corresponding to an intersection between a vertical plane of symmetry of the aircraft and an exterior surface of the fuselage comprises:
• a simple curvature between the fuselage nose and the cockpit bulkhead, and curvature inversion between the cockpit bulkhead and the joining cross section so that the lower profile has a local extremum at the bottom, said local extremum determining an intermediate cross section between the said cockpit bulkhead and the said joining cross section,
• and wherein upper shapes of the front part determine an upper profile of the fuselage said upper profile, between the fuselage nose and the intermediate cross section, having a simple curvature and being essentially symmetrical, with respect to an axis parallel to the longitudinal axis and passing through the fuselage nose, imparting a general ovoid shape to the fuselage in front of the lower bulge.