A high efficiency hydrogen fuel system for an aircraft at high altitude which utilizes compressors to compress air to a sufficiently high pressure for the fuel cell. Liquid hydrogen is compressed and then utilized in heat exchangers to cool the compressed air, maintaining the air at a temperature low enough for the fuel cell. The hydrogen is also used to cool the fuel cell as it is also depressurized prior to its entry in the fuel cell cycle. A water condensation system allows for water removal from the airstream to reduce impacts to the atmosphere. The hydrogen fuel system may be used with VTOL aircraft, which may allow them to fly at higher elevations. The hydrogen fuel system may be used with other subsonic and supersonic aircraft, such as with asymmetric wing aircraft.

Renewable fuel power systems for vehicles, such as aircraft, are provided. For example, a system includes a storage tank, a reactor module, a heat exchanger unit, and a combustion engine. The storage tank is configured to store ammonia in liquid form. The reactor module is in fluid communication with the storage tank. The reactor module is configured to extract hydrogen from the ammonia, and output fuel which includes the extracted hydrogen. The heat exchanger unit is configured to heat the ammonia which flows from the storage tank to an input of the reactor module, using heat which is extracted from the fuel that is output from the reactor module. The combustion engine is configured to combust the fuel provided by the reactor module, to thereby produce mechanical power.

Renewable fuel power systems for vehicles, such as aircraft, are provided. For example, a system includes a storage tank, a reactor module, a heat exchanger unit, and a combustion engine. The storage tank is configured to store ammonia in liquid form. The reactor module is in fluid communication with the storage tank. The reactor module is configured to extract hydrogen from the ammonia, and output fuel which includes the extracted hydrogen. The heat exchanger unit is configured to heat the ammonia which flows from the storage tank to an input of the reactor module, using heat which is extracted from the fuel that is output from the reactor module. The combustion engine is configured to combust the fuel provided by the reactor module, to thereby produce mechanical power.

A method of determining one or more fuel characteristics of an aviation fuel for powering a gas turbine engine of an aircraft includes: measuring one or more trace substance parameters of the fuel, the one or more trace substance parameters each associated with a respective trace substance in the fuel; and determining one or more fuel characteristics of the fuel based on the one or more trace substance parameters. Further, a fuel characteristic determination system, a method of operating an aircraft, and an aircraft.

A propulsion system for an aircraft, which has a chassis, a propeller able to move in rotation about an axis of rotation, a main gear as one with the propeller, an electric generator, at least one linear electric motor having a fixed element and a slider able to move in translation, for each linear electric motor, a secondary gear meshing with the main gear and mounted to be able to move in rotation about an axis of rotation perpendicular to the axis of rotation, and a rod of which one end is articulated on the corresponding slider and of which the other end is articulated on the corresponding secondary gear at an articulation that is offset with respect to the axis of rotation of the secondary gear.

In the method for propelling an aircraft, to obtain electric energy, a fuel is combusted, and an electric machine is used, wherein the fuel is used to cool at least one part of the electric machine and contains natural gas. The propulsion system is configured to propel an aircraft, in particular according to the above-mentioned method. The propulsion system has an electric machine configured to obtain electric energy by combusting a fuel. The propulsion system further includes a natural gas tank configured to supply the fuel formed with natural gas, and a cooling device configured to cool at least one part of the electric machine. The aircraft has such a propulsion system.

In the method for propelling an aircraft, to obtain electric energy, a fuel is combusted, and an electric machine is used, wherein the fuel is used to cool at least one part of the electric machine and contains natural gas. The propulsion system is configured to propel an aircraft, in particular according to the above-mentioned method. The propulsion system has an electric machine configured to obtain electric energy by combusting a fuel. The propulsion system further includes a natural gas tank configured to supply the fuel formed with natural gas, and a cooling device configured to cool at least one part of the electric machine. The aircraft has such a propulsion system.

A pipeline including at least first and second portions, each comprising outer and inner pipes, at least one coupling system connecting the first and second portions and including at least a downstream flange ring connected to at least one of the outer and inner pipes of the first portion, at least an upstream flange ring connected to at least one of the outer and inner pipes of the second portion, connecting elements connecting the upstream and downstream flange rings, first and second annular seals interposed between the upstream and downstream flange rings and configured to delimit, with the upstream and downstream flange rings, a buffer space containing an atmosphere, the pipeline comprising at least one leak detection system configured to determine at least one characteristic of the atmosphere of the buffer space.

A pipeline including at least first and second portions, each comprising outer and inner pipes, at least one coupling system connecting the first and second portions and including at least a downstream flange ring connected to at least one of the outer and inner pipes of the first portion, at least an upstream flange ring connected to at least one of the outer and inner pipes of the second portion, connecting elements connecting the upstream and downstream flange rings, first and second annular seals interposed between the upstream and downstream flange rings and configured to delimit, with the upstream and downstream flange rings, a buffer space containing an atmosphere, the pipeline comprising at least one leak detection system configured to determine at least one characteristic of the atmosphere of the buffer space.

A hydrogen tank for aircraft, including an inner vessel configured to contain hydrogen, first and second outer jacket domes having a semi-spherical shape and first L-shaped ends, a first cylindrical outer jacket established on top of the first and second outer jacket domes, a second cylindrical outer jacket established in the bottom of the first and second outer jacket domes. The first and second cylindrical outer jackets include second L-shaped ends. The first and second L-shaped ends form L-shaped junctions to attach the first and second outer jacket domes to the first and second cylindrical outer jackets.