An autonomous propeller propulsion system for an aircraft. The autonomous system comprises a chassis with first attachment systems which engage with second attachment systems of the wing to ensure detachable attachment of the autonomous system, a fuel cell attached to the chassis, an electric motor attached to the chassis and having an output shaft, a propshaft rotated by the output shaft, a propeller attached to the propshaft, a controller converting an electric current delivered by the fuel cells into an electric current delivered to the electric motor, a hydrogen feed duct and an air feed duct, a set of auxiliary equipment, and a first connection arrangement, which connects with a second connection arrangement of the aircraft.

A fuel containment system for an aircraft is provided. The fuel containment system comprises an upper fuel barrier under a cabin floor, an aft wheel well bulkhead, an aft fuel barrier opposite the aft wheel well bulkhead, a lower fuel barrier associated with a cargo floor, and a lower fuselage skin panel. A fuel tank is created by the upper fuel barrier, the aft wheel well bulkhead, the aft fuel barrier, the lower fuel barrier, and the lower fuselage skin. The fuel tank is integrated into the aircraft and existing structural components are sealed to prevent fuel from leaking out of the integrated fuel tank.

A fuel containment system for an aircraft is provided. The fuel containment system comprises an upper fuel barrier under a cabin floor, an aft wheel well bulkhead, an aft fuel barrier opposite the aft wheel well bulkhead, a lower fuel barrier associated with a cargo floor, and a lower fuselage skin panel. A fuel tank is created by the upper fuel barrier, the aft wheel well bulkhead, the aft fuel barrier, the lower fuel barrier, and the lower fuselage skin. The fuel tank is integrated into the aircraft and existing structural components are sealed to prevent fuel from leaking out of the integrated fuel tank.

In an aspect, an aircraft fueling apparatus is disclosed. The apparatus includes at least a container comprising a fuel tank configured to store liquified gas fuel. The apparatus may also include a translocation device configured to carry the at least a container. An orientation guidance track may also be included in the apparatus. The orientation guidance track may be configured to direct a movement of the translocation device to a first position.

In an aspect, an aircraft fueling apparatus is disclosed. The apparatus includes at least a container comprising a fuel tank configured to store liquified gas fuel. The apparatus may also include a translocation device configured to carry the at least a container. An orientation guidance track may also be included in the apparatus. The orientation guidance track may be configured to direct a movement of the translocation device to a first position.

A cryogenic fuel auxiliary power system for an engine may include a cryogenic fuel supply, a first valve in fluid communication with the cryogenic fuel supply and configured to control a fuel flow, a first heat exchanger, configured to receive the fuel flow, in fluid communication with the first valve and a combustion chamber of the engine, and a fuel cell in fluid communication between the first valve and the first heat exchanger.

A cryogenic fuel auxiliary power system for an engine may include a cryogenic fuel supply, a first valve in fluid communication with the cryogenic fuel supply and configured to control a fuel flow, a first heat exchanger, configured to receive the fuel flow, in fluid communication with the first valve and a combustion chamber of the engine, and a fuel cell in fluid communication between the first valve and the first heat exchanger.

A wing drop fuel tank it is provided comprising a rigid external casing 1 and a second tank 2 arranged inside said rigid casing 1, said second tank 2 being made of flexible material. A production process of said wing drop tank it is also provided which comprises the following steps: construction of two rigid half-shells 10 and 11, and the subsequent mutual coupling of the former creates a single rigid structure 1; making of a first port and a second port at the upper part of the half-shell 10, said second port having same size of a fuel filling flange 23 on said tank 1; inserting of a second tank 2 made of a flexible material through said first port in said first tank 1; and applying a closing plate 12 at said upper port, said closing plate 12 being removably locked on said tank 1 by means of clamping screws 13 which engage with threaded holes 22 made on a flange 21 integral with said second tank 2.

A metallic structure defines ribs and a skin supported by the ribs. The ribs may be defined by metal strips and the skin may be attached to the ribs. Alternatively, the skin may be defined by a plurality of tiles and the ribs may be defined by flanges of each of the plurality of tiles that cooperate to define the ribs. Tiles may be attached to separate rib lattice. Structurally weak locations at nodes where ribs intersect may be reinforced. The components may be brazed together and the stiffness of adjacent locations in the structure adjusted in the brazing operation to reduce the difference in stiffness and to reduce resulting stress risers. The metallic structure may be armored using metal foam to absorb the energy of a projectile.

Duct stringers for aircraft wing boxes. The duct stringer comprises a base, a pair of sidewalls projecting from the base in a spaced-apart relationship, and a cap wall that extends between and interconnects the pair of sidewalls, with the cap wall being positioned spaced apart from the base by the pair of sidewalls. The duct stringer further comprises an ovaloid vent formed in the cap wall. The ovaloid vent comprises a perimeter that circumscribes an aperture and that defines a closed shape. The perimeter comprises a pair of curved end regions opposed to one another and that each arc at least substantially through 180 degrees. Each curved end region comprises a non-uniform radius of curvature.