A liquid tank system comprises a main liquid tank, an outlet communicating between a fluid circuit and the main liquid tank, an inlet communicating between the fluid circuit and the main liquid tank, and an auxiliary cavity. First vent passage and second vent passage(s) communicate between the main liquid tank and the auxiliary cavity and allows liquid and gas to flow from the main liquid tank to the auxiliary cavity. The second vent passage has a flow control device regulating flow through the second vent passage and having a set point at which it allows liquid and gas to flow from the main liquid tank to the auxiliary cavity only when a pressure in the main liquid tank is beyond a threshold. The liquid tank system has an attitude envelope in which the liquid tank system is configured such that, in use, the flow control device blocks flow through the second vent passage when an end of the first vent passage in the main liquid tank is above a liquid level, and the flow control device allows gas and/or fluid flow through the second vent passage when main fluid tank pressure is above the threshold and the end of the first vent passage in the main liquid tank is below the liquid level.

An aircraft fuel system includes a first pump system that is mechanically driven and in selective fluid communication with a fuel tank and a fuel nozzle of an engine. The first pump system is configured to pump fuel to the fuel nozzles in a high flow rate condition and to be starved or nearly starved of fuel in a low flow rate condition. The aircraft fuel system includes a second pump system including an electric motor. The second pump system is in fluid communication with the fuel tank and the fuel nozzle to pump fuel from the fuel tank to the fuel nozzles. The second pump system is driven by the electric motor and is configured to pump flow in both the high flow rate condition and the low flow rate condition.

An aircraft fuel system includes a first pump system that is mechanically driven and in selective fluid communication with a fuel tank and a fuel nozzle of an engine. The first pump system is configured to pump fuel to the fuel nozzles in a high flow rate condition and to be starved or nearly starved of fuel in a low flow rate condition. The aircraft fuel system includes a second pump system including an electric motor. The second pump system is in fluid communication with the fuel tank and the fuel nozzle to pump fuel from the fuel tank to the fuel nozzles. The second pump system is driven by the electric motor and is configured to pump flow in both the high flow rate condition and the low flow rate condition.

A method of transmitting energy comprises a production step of producing hydrogen, a first transferring step of transferring the hydrogen into a tank at a first location, a transporting step of transporting the tank to a second location using an aircraft, a second transferring step of transferring a transmitted portion of the hydrogen out of the tank at the second location, an oxidation step of oxidizing the transmitted portion to generate thermal, electrical or mechanical energy. A liquefaction step of converting the hydrogen to liquid hydrogen is carried out prior to the first transferring step, such that the hydrogen transferred into the tank is liquid hydrogen, a gasification step of gasifying the transmitted portion is carried out after the second transferring step, such that the transmitted portion is liquid in the second transferring step and gaseous in the oxidation step, and the aircraft is an airplane.

A method of transmitting energy comprises a production step of producing hydrogen, a first transferring step of transferring the hydrogen into a tank at a first location, a transporting step of transporting the tank to a second location using an aircraft, a second transferring step of transferring a transmitted portion of the hydrogen out of the tank at the second location, an oxidation step of oxidizing the transmitted portion to generate thermal, electrical or mechanical energy. A liquefaction step of converting the hydrogen to liquid hydrogen is carried out prior to the first transferring step, such that the hydrogen transferred into the tank is liquid hydrogen, a gasification step of gasifying the transmitted portion is carried out after the second transferring step, such that the transmitted portion is liquid in the second transferring step and gaseous in the oxidation step, and the aircraft is an airplane.

A composition including 85.00-99.00 wt. % of a single Nylon polymer; 0.25-5.00 wt. % of conductive nanomaterials; 0.25-5.00 wt. % of a dielectric filler comprising an inorganic, non-conductive, non-platelet nanomaterial selected from alumina nanoparticles, alumina nanotubes, aluminum oxide nanoparticles, silica nanoparticles, boron nitride nanoparticles, boron nanotubes, fumed silica, fumed alumina, and mixtures of one or more of these; and 0.25-5.00 wt. % of a dispersing agent.

A composition including 85.00-99.00 wt. % of a single Nylon polymer; 0.25-5.00 wt. % of conductive nanomaterials; 0.25-5.00 wt. % of a dielectric filler comprising an inorganic, non-conductive, non-platelet nanomaterial selected from alumina nanoparticles, alumina nanotubes, aluminum oxide nanoparticles, silica nanoparticles, boron nitride nanoparticles, boron nanotubes, fumed silica, fumed alumina, and mixtures of one or more of these; and 0.25-5.00 wt. % of a dispersing agent.

The application provides an autonomous refueling vehicle for a hydrogen-electric aircraft, which includes two or more wings. The wings are provided with one or more removable electric propulsion pods. The autonomous refueling vehicle includes a hydrogen refueling module adapted to connect to the propulsion pods and to a hydrogen source. The autonomous refueling vehicle includes also includes a propulsion pod handling device, which is adapted to remove the propulsion pod from the wings and to position the propulsion pods on the hydrogen refueling module such that the propulsion pods are connected to the hydrogen refueling module. The autonomous refueling vehicle is also adapted to autonomously move itself to the hydrogen source to allow the hydrogen refueling module to removably connect to the hydrogen source for refueling of the propulsion pods.

The application provides an autonomous refueling vehicle for a hydrogen-electric aircraft, which includes two or more wings. The wings are provided with one or more removable electric propulsion pods. The autonomous refueling vehicle includes a hydrogen refueling module adapted to connect to the propulsion pods and to a hydrogen source. The autonomous refueling vehicle includes also includes a propulsion pod handling device, which is adapted to remove the propulsion pod from the wings and to position the propulsion pods on the hydrogen refueling module such that the propulsion pods are connected to the hydrogen refueling module. The autonomous refueling vehicle is also adapted to autonomously move itself to the hydrogen source to allow the hydrogen refueling module to removably connect to the hydrogen source for refueling of the propulsion pods.

A method of managing evaporated cryogenic fuel in a storage tank of a cryogenic fuel system of an aircraft and an aircraft having at least one turbine engine providing propulsive force for the aircraft and a cryogenic fuel system including a passively cooled cryogenic fuel storage tank located within the aircraft, a pressure vent fluidly coupled to the cryogenic fuel storage tank and exhausting evaporated gas from the cryogenic fuel to define a natural gas vent stream, and a catalytic converter fluidly coupled to the pressure vent.