Abstract: A breathing gas supply system for an aircraft includes a plurality of oxygen concentrating apparatus, each of which in use, is operable to supply oxygen enriched gas to a breathing gas supply. Each oxygen concentrating apparatus includes at least two active molecular sieve beds which are operable so that while one sieve bed is adsorbing non-oxygen gas from a pressurized gas supply, the or another bed is being purged of non-oxygen gas by subjecting the bed to lower pressure. Each oxygen concentrating apparatus includes an oxygen enriched gas flow control device which permits the flow of oxygen enriched gas produced by the oxygen concentrating apparatus to the breathing gas supply and permits a restricted flow of oxygen enriched gas from the breathing gas supply to the oxygen concentrating apparatus. Oxygen enriched gas produced by the adsorbing sieve bed flows direct to the bed being purged.

Abstract: A breathing gas supply system for an aircraft includes a plurality of oxygen concentrating apparatus, each of which in use, is operable to supply oxygen enriched gas to a breathing gas supply. Each oxygen concentrating apparatus includes at least two active molecular sieve beds which are operable so that whilst one sieve bed is adsorbing non-oxygen gas from a pressurized gas supply, the or another bed is being purged of non-oxygen gas by subjecting the bed to lower pressure. Each oxygen concentrating apparatus includes an oxygen enriched gas flow control device which permits the flow of oxygen enriched gas produced by the oxygen concentrating apparatus to the breathing gas supply and permits a restricted flow of oxygen enriched gas from the breathing gas supply to the oxygen concentrating apparatus. Oxygen enriched gas produced by the adsorbing sieve bed flows direct to the bed being purged.

Abstract: A fluid control valve for use in a system for inflating an anti-G garment. The valve includes an elongate chamber in which a valve member is moveable. The chamber has first and second axial ends. An inlet opening in a chamber wall provides for the flow of fluid into the chamber. A valve edge is provided at the second end of the chamber to form an outlet. The valve member has a first portion which closes the first chamber end and is moveable in the chamber between the inlet opening and the first chamber end, an intermediate portion which has a cross sectional area less than that of the chamber wall to permit the inflow of fluid to the chamber, and a second portion including a flow control device which co-operates with the valve edge to control fluid flow from the valve.

Abstract: An environmental control system for conditioning air in a vehicle compartment, such as an aircraft cabin. Cool expanded higher-pressure air from a turbine is mixed with recirculated warmer, lower pressure air from the compartment. The air is mixed and recirculated by a jet pump which includes an inlet section, an outlet section, a diffuser section and a mixing section. The mixing section includes a plurality of separate mixing chambers. The diffuser section includes diffusers for receiving mixed gases from each of the mixing chambers. The outlet section receives the mixed gases which are then conveyed to the compartment. The inlet section includes for each of the mixing chambers, a primary nozzle for introducing the higher-pressure air into a respective mixing chamber, and a secondary nozzle for introducing the lower pressure air to a respective mixing chamber.

Abstract: A method of controlling an apparatus for separating product gas and non product gas from an air supply, the concentration of the product gas produced by the apparatus being variable depending on a control signal from a controller and the efficiency of the apparatus in producing product gas depending upon an environmental parameter, the method including sensing the oxygen concentration in the product gas produced by the apparatus, determining an instantaneous demand for oxygen concentration in the product gas, providing to the controller a process variable signal indicative of the sensed concentration of the oxygen in the product gas, and providing to the controller a demand input signal indicative of the demand, sensing the environmental parameter and providing an environmental parameter input signal to the controller, comparing the process variable signal and the demand signal to generate an error signal indicative of a change in oxygen concentration in the product gas required to match the instantaneous dem

Abstract: A hydraulic heating apparatus includes a body having an inlet for high pressure fluid, and an outlet for heated fluid, a chamber within the body and a flow path for the high pressure fluid between the inlet and the chamber. The high pressure fluid flows through a restriction in the flow path between the inlet and the chamber whereby the apparatus becomes heated. The working fluid flowing from the inlet to the chamber must pass through an orifice which is closable by a linearly acting closure structure. The closure structure is urged to a position in which the closure structure closes the orifice when the pressure of the high pressure fluid is below a threshold pressure. The closure structure includes a thermally sensitive material which expands in response to increasing temperature to close the orifice in response to a temperature above a threshold temperature.

Abstract: An environmental control system for conditioning air in a vehicle compartment, such as an aircraft cabin. Cool expanded higher-pressure air from a turbine is mixed with recirculated warmer, lower pressure air from the compartment. The air is mixed and recirculated by a jet pump which includes an inlet section, an outlet section, a diffuser section and a mixing section. The mixing section includes a plurality of separate mixing chambers. The diffuser section includes diffusers for receiving mixed gases from each of the mixing chambers. The outlet section receives the mixed gases which are then conveyed to the compartment. The inlet section includes for each of the mixing chambers, a primary nozzle for introducing the higher-pressure air into a respective mixing chamber, and a secondary nozzle for introducing the lower pressure air to a respective mixing chamber.

Abstract: A fluid control valve for use in a system for inflating an anti-G garment. The valve includes an elongate chamber in which a valve member is moveable. The chamber has first and second axial ends. An inlet opening in a chamber wall provides for the flow of fluid into the chamber. A valve edge is provided at the second end of the chamber to form an outlet. The valve member has a first portion which closes the first chamber end and is moveable in the chamber between the inlet opening and the first chamber end, an intermediate portion which has a cross sectional area less than that of the chamber wall to permit the inflow of fluid to the chamber, and a second portion including a flow control device which co-operates with the valve edge to control fluid flow from the valve.

Abstract: A method of providing gas to a system which separates from a pressurized supply gas, product gas, includes conditioning the supply gas by both cooling and drying the supply gas.

Abstract: A hydraulic heating apparatus includes a body having an inlet for high pressure fluid, and an outlet for heated fluid, a chamber within the body and a flow path for the high pressure fluid between the inlet and the chamber. The high pressure fluid flows through a restriction in the flow path between the inlet and the chamber whereby the apparatus becomes heated. The working fluid flowing from the inlet to the chamber must pass through an orifice which is closable by a linearly acting closure structure. The closure structure is urged to a position in which the closure structure closes the orifice when the pressure of the high pressure fluid is below a threshold pressure. The closure structure includes a thermally sensitive material which expands in response to increasing temperature to close the orifice in response to a temperature above a threshold temperature.

Abstract: An ionic conduction device of the kind including a tri-layer including an electrolytic membrane having a pair of opposed surfaces, and a gas permeable electrode in contact with each opposed surface. The device has a first gas flow path for a first gas across one of the opposed surfaces, and second gas flow path for a second gas across the one of the opposed surfaces, and a third gas flow path for a third gas along the other of the opposed surfaces of the membrane. The device includes a fourth flow path through the device for a heat exchanging fluid. The fourth flow path bringing the heat exchanging fluid into heat exchange relationship with the tri-layer.

Abstract: Apparatus for testing an article under a prevailing force of up to a number of times the gravitational force G, the apparatus including a driving device for imparting vibration to the article, the driving device including an element for connection to the article, the element being operable in a direction which is subject to at least a component of the prevailing force, wherein there is provided a balancing member mounted so as to be subject to at least the component of the prevailing force, the balancing member being connected to the element so as to apply to it a force in opposition to the prevailing force component thereon.

Abstract: A breathing gas supply system for supplying breathable gas in an aircraft includes an oxygen enriching apparatus which is operable in at least two modes to provide product gas with varying oxygen concentrations. A first feed line feeds more highly enriched product gas to one or more breathing gas outlets, and a second feed line feeds less highly enriched product gas e.g. to an aircraft cabin for breathing during normal high altitude flight. A control means controls oxygen enrichment apparatus to provide highly enriched product gas to the breathing gas outlet or outlets in the first mode of operation or less highly enriched product gas e.g. to the cabin for normal breathing, and controls a diverter valve. Which directs the product gas to the respective feed line.

Abstract: A closed loop air conditioning system for an aircraft includes a compressor stage including at least one power driven compressor, for compressing working fluid, a first expansion turbine over which compressed working fluid is expanded and cooled, a first heat load heat exchanger in which heat from a first heat load is exchanged to the expanded and cooled working fluid, a second expansion turbine over which working fluid from the first heat exchanger is further expanded and cooled, and a second heat load heat exchanger in which heat from a second heat load is exchanged to the further expanded and cooled working fluid.

Abstract: A method of installing a molecular sieve bed gas enrichment system in a vehicle such as an aircraft. A system controller, a product gas distribution conduit, a high pressure gas supply conduit which extends from a high pressure gas source, and a plurality of molecular sieve beds are installed in the vehicle. Each sieve bed has a first port which delivers product gas through a check valve to an outlet duct. Each sieve bed also includes a second port connected to a valve assembly which is controlled by the system controller to connect the second port either to a gas supply duct during a charging phase or to a venting duct during a venting phase. The outlet duct for each sieve bed is connected to the product gas distribution conduit, and the gas supply duct for each sieve bed is connected to the high pressure gas supply conduit.

Abstract: A method of controlling a gas adsorption apparatus including a sieve bed containing molecular sieve bed material, the bed being cyclically operable in a charge mode to adsorb non-product gas from an air supply thereby to increase the concentration of a product gas in a product gas supply which passes to a product gas line and in a vent mode to desorb the adsorbed non-product gas which passes to a non-product gas line, and there being a passage to permit a restricted amount only of the product gas supply to pass from the product gas supply line to the bed when operating in vent mode, and wherein the method includes operating a variable flow device to permit an increased amount of the product gas supply to pass to the bed when operating in vent mode, under predetermined conditions.

Abstract: A gas bottle assembly includes a container for containing a pressurized gas, and an operating head, the operating head including a valve member which in the absence of any demand for the gas, is positioned close to a valve seat such as to permit only a minimal flow of gas from the container past the valve seat, and an actuator moveable to move the valve member away from the valve seat thereby to permit a greater flow of gas past the valve seat, to an outlet for use, and wherein the actuator includes a plunger with which the valve member is integral or to which the valve member is affixed, and the actuator includes a piston part which is movable in a piston chamber in one direction in response an actuator spring acting at a first side of the piston part, to move the valve member away from the seat, and in an opposite direction in response to a combination of gas pressure and a valve return spring which is located in the piston chamber at a second opposite side of the piston part to the actuator spring.

Abstract: Cooling apparatus for use on a vehicle. The apparatus includes a heat exchanger in which heat is removed from a heat load by a coolant, and first and second coolant supplies. The first coolant supply is adapted to receive a first coolant and to supply the first coolant to the heat exchanger. The first coolant is available during normal vehicle operations. The second coolant supply is adapted to receive a second coolant and to supply the second coolant to the heat exchanger. The second coolant is supplied by a fluid supply and is unavailable during normal vehicle operation.

Abstract: A life-support system for an aircraft B includes a first oxygen supply apparatus A operable to provide a limited supply of first product gas being one of pure oxygen and oxygen enriched gas, to a breathing gas supply apparatus 12, 13, 14, and a second oxygen supply apparatus B operable to supply a durable supply of second product gas which is an oxygen enriched gas containing a lower concentration of oxygen than that in the first product gas, to the breathing gas supply apparatus 12, 13, 14, wherein the second product gas is supplied as the pressure which is higher than that at which the first product gas is supplied to the breathing gas supply apparatus 12, 13, 14.

Abstract: A method of balancing the supply of bleed air from a plurality of gas turbine engines, there being an air bleed line from each of the engines to a common distribution line which distributes the bled air to at least one ancillary system, each air bleed line including a control valve which is controllable by a controller to vary the flow rate of air bled from the associated engine, the method including providing to the controller a demand signal indicative of the demand for bleed air by the ancillary system, sensing air pressure in the distribution line and comparing the demand signal with the sensed air pressure to derive a command signal, flow rates the air pressure individually in each of the air bleed lines from the engines with respective air flow rate sensors which provide air flow rate signals to the controller, comparing the air flow rates in each of the air bleed lines to derive individual flow matching signals for each of the engines, comparing each of the flow matching signals to the command signal t