An aircraft fuel system including at least one fuel tank, a source of inerting gas, an inlet for introducing the inerting gas into the at least one fuel tank, and a vent system arranged to allow the inward and outward venting of air from the fuel tank. In embodiments, the vent system includes a vent, an inward vent pressure valve disposed between the vent and the at least one fuel tank and configured to enable the at least one fuel tank to increase by a predetermined pressure over ambient air pressure, and an outward vent pressure valve disposed between the at least one fuel tank and the vent and configured to enable the at least one fuel tank to decrease by a predetermined pressure below ambient air pressure.

An aircraft fuel system including at least one fuel tank, a source of inerting gas, an inlet for introducing the inerting gas into the at least one fuel tank, and a vent system arranged to allow the inward and outward venting of air from the fuel tank. In embodiments, the vent system includes a vent, an inward vent pressure valve disposed between the vent and the at least one fuel tank and configured to enable the at least one fuel tank to increase by a predetermined pressure over ambient air pressure, and an outward vent pressure valve disposed between the at least one fuel tank and the vent and configured to enable the at least one fuel tank to decrease by a predetermined pressure below ambient air pressure.

A fuel supply system for an aircraft includes a fuel tank configured to supply fuel to an engine of an aircraft, a boost pump in operational communication with the fuel tank, wherein the boost pump is configured to control at least one of a fuel level and a fuel pressure in the fuel tank, and an electronic controller in communication with the boost pump and configured to control the boost pump. The electronic controller is configured to receive received information including (i) fuel information, (ii) flight information, and (iii) aircraft information, and configured to control the boost pump based on the received information.

A fuel supply system for an aircraft includes a fuel tank configured to supply fuel to an engine of an aircraft, a boost pump in operational communication with the fuel tank, wherein the boost pump is configured to control at least one of a fuel level and a fuel pressure in the fuel tank, and an electronic controller in communication with the boost pump and configured to control the boost pump. The electronic controller is configured to receive received information including (i) fuel information, (ii) flight information, and (iii) aircraft information, and configured to control the boost pump based on the received information.

A fuel supply system for an aerial vehicle includes: a plurality of fixed tanks storing fuel; a variable tank provided in a fixed tank of the plurality of fixed tanks and storing fuel; a fuel supply flow path, a first end of which is connected to the variable tank and passing through the plurality of fixed tanks; and a fuel pump provided in a fixed tank which does not have the variable tank, an outlet side of the fuel pump being connected to the fuel supply flow path. According to the fuel supply system, continuous fuel supply is performed despite the change of the attitude or acceleration of an aerial vehicle, sufficient fuel is stored, and constraints on fuel tank design are minimized.

A fuel supply system for an aerial vehicle includes: a plurality of fixed tanks storing fuel; a variable tank provided in a fixed tank of the plurality of fixed tanks and storing fuel; a fuel supply flow path, a first end of which is connected to the variable tank and passing through the plurality of fixed tanks; and a fuel pump provided in a fixed tank which does not have the variable tank, an outlet side of the fuel pump being connected to the fuel supply flow path. According to the fuel supply system, continuous fuel supply is performed despite the change of the attitude or acceleration of an aerial vehicle, sufficient fuel is stored, and constraints on fuel tank design are minimized.

A dual lock flow gate includes a valve with a flapper which may be fixed and/or locked in various positions for example to prevent fluid flow in the production string during lowering of the production string in the casing by blocking flow in the production string with the dual lock flow gate or for example to prevent rotation of the pump motor by preventing fluid flow in the production string.

Systems and methods are provided for storage in at least one on-board fuel tank of aircraft fuel under a predetermined pressure and at an internal ambient tank temperature. A passive heat exchanger having an exchanger inlet is fluid-connected to a propulsion engine of the aircraft to receive heated pressurized bleed air therefrom while an exchanger outlet is fluid connected to the fuel tank. The passive heat exchanger is configured to cool the heated pressurized bleed air from the engine by heat transfer to a surrounding environment by radiation and convection so as to supply pressurization air to the fuel tank at the predetermined internal tank pressure and the internal ambient tank temperature. A system controller is provided to provide the fuel tank with pressurized air at a predetermined temperature during various aircraft flight phases.

Systems and methods are provided for storage in at least one on-board fuel tank of aircraft fuel under a predetermined pressure and at an internal ambient tank temperature. A passive heat exchanger having an exchanger inlet is fluid-connected to a propulsion engine of the aircraft to receive heated pressurized bleed air therefrom while an exchanger outlet is fluid connected to the fuel tank. The passive heat exchanger is configured to cool the heated pressurized bleed air from the engine by heat transfer to a surrounding environment by radiation and convection so as to supply pressurization air to the fuel tank at the predetermined internal tank pressure and the internal ambient tank temperature. A system controller is provided to provide the fuel tank with pressurized air at a predetermined temperature during various aircraft flight phases.

A filter system with flow regulation includes a filter interposed along the fluid passageway and a differential valve in fluid series therewith. The valve may use the upstream reference hydraulic pressure at the filter inlet and a downstream hydraulic pressure thereof to generate a valve position that regulates fluid flow along the fluid passageway. This can partially restrict flow and reduce pressure differential across the filter system and effectively closes off flow through the system when pressure differential is high. This may be used in aircraft or other fueling applications to limit flow and cause the operator to change the fuel filter once fuel flow slows to a trickle when the differential valve effectively closes due to higher differential pressure. The valve is also capable of a fully closed position at high pressure differential state.