A liquid containment cell includes an inner layer configured to contain a liquid, an outer layer, and a multilayer self-sealing structure disposed between the inner layer and the outer layer, where the multilayer self-sealing structure includes a plurality of sealing liner layers and further includes at least one slip layer disposed between adjacent sealing liner layers of the plurality of sealing liner layers. The at least one slip layer includes a polyethylene (PE) material, and the at least one slip layer is configured to permit at least one sealing liner layer of the plurality of sealing liner layers to move at least partially into a hole created by a projectile.

A liquid containment cell includes an inner layer configured to contain a liquid, an outer layer, and a multilayer self-sealing structure disposed between the inner layer and the outer layer, where the multilayer self-sealing structure includes a plurality of sealing liner layers and further includes at least one slip layer disposed between adjacent sealing liner layers of the plurality of sealing liner layers. The at least one slip layer includes a polyethylene (PE) material, and the at least one slip layer is configured to permit at least one sealing liner layer of the plurality of sealing liner layers to move at least partially into a hole created by a projectile.

An aircraft comprises a hydrogen-fuelled propulsion system, a plurality of like generally cylindrical hydrogen storage tanks and a conveying system arranged to convey hydrogen from the hydrogen storage tanks to the hydrogen-fuelled propulsion system. The aircraft further comprises a fuselage having a cargo bay (502) including one or more (510A-G) of the plurality of hydrogen storage tanks, the longitudinal axes (511A-G) of the one or more hydrogen storage tanks within the cargo bay extending parallel to the longitudinal axis (501) of the fuselage and lying in one or more planes (595, 597) extending across the width dimension of the cargo bay. The hydrogen storage tanks within the cargo bay have a common aspect ratio R in the range 4.2 ≤ R ≤ 25.7, allowing the volume of space with the cargo bay occupied by stored hydrogen to be maximised or approximately maximised.

An aircraft comprises a hydrogen-fuelled propulsion system, a plurality of like generally cylindrical hydrogen storage tanks and a conveying system arranged to convey hydrogen from the hydrogen storage tanks to the hydrogen-fuelled propulsion system. The aircraft further comprises a fuselage having a cargo bay (502) including one or more (510A-G) of the plurality of hydrogen storage tanks, the longitudinal axes (511A-G) of the one or more hydrogen storage tanks within the cargo bay extending parallel to the longitudinal axis (501) of the fuselage and lying in one or more planes (595, 597) extending across the width dimension of the cargo bay. The hydrogen storage tanks within the cargo bay have a common aspect ratio R in the range 4.2 ≤ R ≤ 25.7, allowing the volume of space with the cargo bay occupied by stored hydrogen to be maximised or approximately maximised.

A combined cooling and humidifying system for a fuel cell system includes a first line strand, second line strand, gas separator, and water feed device. The first line strand has a supply line for feeding water to a heat exchanger of the fuel cell system and a return line for receiving a water-steam mixture from the fuel cell system. The gas separator is in the return line to at least partially separate the steam from the water-steam mixture and provide it at a steam connection. The second line strand has a fluid inlet for feeding a gaseous fluid to the fuel cell system. The steam connection is coupled to the second line strand downstream of the fluid inlet to admix steam with the fluid. The water feed device is coupled to the supply line to compensate for a separating mass flow of steam in the first line strand.

A combined cooling and humidifying system for a fuel cell system includes a first line strand, second line strand, gas separator, and water feed device. The first line strand has a supply line for feeding water to a heat exchanger of the fuel cell system and a return line for receiving a water-steam mixture from the fuel cell system. The gas separator is in the return line to at least partially separate the steam from the water-steam mixture and provide it at a steam connection. The second line strand has a fluid inlet for feeding a gaseous fluid to the fuel cell system. The steam connection is coupled to the second line strand downstream of the fluid inlet to admix steam with the fluid. The water feed device is coupled to the supply line to compensate for a separating mass flow of steam in the first line strand.

A propulsion system comprising a nacelle with an air channel along a longitudinal direction, an electric motor whose output drives a propeller, and a fuel cell, comprising a core outside the air channel, open channels, each of which has an inlet and an outlet opening in the air channel, and, for each open channel, a fuel chamber, an electrolyte between the open channel and the fuel chamber, a cathode, and an anode, each open channel having an inlet surface area which is less than the surface area of an intermediate area between the inlet and the outlet, the surface area of the outlet being smaller than the surface area of the intermediate area. Such a system makes it possible to have the fuel cell close to the electric motor, thereby reducing the lengths of the electrical conductors between them, and consequently improving the operation of the fuel cell.

A propulsion system comprising a nacelle with an air channel along a longitudinal direction, an electric motor whose output drives a propeller, and a fuel cell, comprising a core outside the air channel, open channels, each of which has an inlet and an outlet opening in the air channel, and, for each open channel, a fuel chamber, an electrolyte between the open channel and the fuel chamber, a cathode, and an anode, each open channel having an inlet surface area which is less than the surface area of an intermediate area between the inlet and the outlet, the surface area of the outlet being smaller than the surface area of the intermediate area. Such a system makes it possible to have the fuel cell close to the electric motor, thereby reducing the lengths of the electrical conductors between them, and consequently improving the operation of the fuel cell.

In order to improve liquid hydrogen storage on aircraft, a liquid hydrogen tank is integrated into the fuselage of the aircraft. At least one portion of the tank wall is formed by specially adapted tank skin panels and/or a pressure bulkhead. The parts forming the tank wall are strengthened to contain a tank pressure of about 3 bar.

In order to improve liquid hydrogen storage on aircraft, a liquid hydrogen tank is integrated into the fuselage of the aircraft. At least one portion of the tank wall is formed by specially adapted tank skin panels and/or a pressure bulkhead. The parts forming the tank wall are strengthened to contain a tank pressure of about 3 bar.