Abstract: An air conditioning pack management system for controlling distribution of a predetermined amount of conditioned air from a system comprising two or more air conditioning packs, the pack management system comprising a management unit arranged to proportion the predetermined amount of conditioned air to be provided by one or more of the two or more packs based on the respective operating efficiencies of the packs or other pre-selected metrics.

Abstract: An aircraft environmental control system includes a bleed air input and a RAM air input, heat exchanger means for receiving bleed air from the bleed air input and RAM air from the RAM air input and using the RAM air to cool the bleed air, and ejector arranged to receive bleed air from the bleed air input at a nozzle shaped to reduce the pressure of the received bleed air such as to create a low pressure area in the ejector. The ejector has a port arranged such that ambient air is drawn into the ejector due to the low pressure area in the ejector. The ambient air is mixed with bleed air to provide mixed air that is further pressurised and conditioned and combined with the cooled bleed air provided to the aircraft.

Abstract: Fibre optics for distributed environmental condition and/or air quality sensing such as, but not limited to, sensing air quality in enclosed areas of an aircraft such as the passenger cabin. Fibre optics can be used for sensing and for communication and are therefore well suited to the distributed sensing of environmental conditions such as temperature, relative humidity, gas and particulate composition within spaces of the aircraft e.g. the cabin, cargo space, cockpit, electronics bay etc. and in related systems such as the environmental control system (ECS), the cabin recirculation system, bleed air system etc.

Abstract: An aircraft environmental control system includes means for mixing and conditioning bleed air from a bleed air input and recirculation air from an aircraft interior to provide mixed, conditioned air to the aircraft interior. The system also includes a first contaminant removal device and a second contaminant removal device arranged in a path of at least part of the recirculation air, prior to the means for mixing and conditioning, and a valve (SV1) arranged to alternate flow of recirculation air through the first and second contaminant removal devices.

Abstract: An air quality sensor includes a detector element array, a processor operatively connected to the detector element array, and a memory. The memory is disposed in communication with the processor and has instructions recorded on the memory that, when read by the processor, cause the processor to execute certain operations including measuring electrical resistance of one of more detector element of the detector element array. A difference is calculated between the measured resistance and a reference resistance, and a determination is made of presence or absence of a contaminant in air communicated to the detector element array from an atmosphere of an aircraft cabin based on the difference between the measured resistance and the reference resistance. Aircraft and methods of monitoring air quality also described.

Abstract: A method and system for controlling fresh air flow into a controlled environment are disclosed herein. The method comprises: measuring, using a sensor, a predetermined property in the controlled environment; estimating, by a controller, a number of people inside the controlled environment based on the measured property, and setting, by the controller, a rate of fresh air flow to the controlled environment based at least in part on the estimated number of people inside the controlled environment.

Abstract: An aircraft environmental control system comprising a fresh air input and a RAM air input, heat exchanger means for receiving fresh air from the fresh air input and RAM air from the RAM air input and using the RAM air to cool the fresh air, and means for providing the cooled fresh air to a cabin of the aircraft, the system further comprising means for feeding back exhaust air emitted from the interior of the aircraft to combine with the RAM air to further cool the fresh air, whereby the heat exchanger means comprises a main heat exchanger and a primary heat exchanger; wherein the main heat exchanger comprising a main heat exchanger cooling fluid inlet, a main heat exchanger cooling fluid outlet and a main heat exchanger bleed air inlet, the cooling fluid working to cool bleed air in the main heat exchanger.

Abstract: An environmental control system that includes a first environmental control system pack, a first recirculation fan assembly, and a cabin air sensor unit. The first environmental control system pack is arranged to provide conditioned air to an aircraft cabin. The first recirculation fan assembly is arranged to recirculate a first cabin air fluid flow back to the aircraft cabin. The cabin air sensor unit is arranged to provide a first air quality signal indicative of an air quality of the first cabin air fluid flow to a controller.

Abstract: A heat exchanger is disclosed. The heat exchanger includes a hollow tube including a first aluminum alloy extending along an axis from a tube inlet to tube outlet. A first plurality of fins including a second aluminum alloy extends outwardly from an outer surface of the tube. A second plurality of fins including a third aluminum alloy extends outwardly from the outer surface of the tube, interspersed along the axis with the fins including the second aluminum alloy. The third aluminum alloy is less noble than each of the first aluminum alloy and the second aluminum alloy, and includes an alloying element selected from tin, indium, gallium, or combinations thereof. A first fluid flow path is disposed through hollow tube from the tube inlet to the tube outlet. A second fluid flow path is disposed across an outer surface of the hollow tube through spaces between adjacent fins.

Abstract: An aircraft environmental control system comprising a bleed air or compressed ambient air input and a RAM air input, heat exchanger means for receiving bleed air from the bleed air input and RAM air from the RAM air input and using RAM air to cool the bleed air, and means for providing the cooled bleed air to an interior of the aircraft; the system further comprising means for feeding back exhaust air emitted from the interior of the aircraft to combine with the RAM air to further cool the bleed air or compressed ambient air.

Abstract: A personal aircraft seat air treatment system may include an air blower, a ventilation output component installed within a passenger compartment, and a treatment component fluidically coupled to the air blower and the ventilation output component. The air blower may be configured to receive cabin air from a cabin air ventilation system installed in an aircraft cabin. The ventilation output component may be configured to provide treated air to a breathing area of a passenger proximate to an aircraft seat installed in the passenger compartment. The treatment component may be fluidically coupled to the air blower and the ventilation output component. The treatment component may be configured to receive the cabin air from the air blower and treat the cabin air to generate the treated air.

Abstract: A heat exchanger is disclosed. The heat exchanger includes a hollow tube including a first aluminum alloy extending along an axis from a tube inlet to tube outlet. A first plurality of fins including a second aluminum alloy extends outwardly from an outer surface of the tube. A second plurality of fins including a third aluminum alloy extends outwardly from the outer surface of the tube, interspersed along the axis with the fins including the second aluminum alloy. The third aluminum alloy is less noble than each of the first aluminum alloy and the second aluminum alloy, and includes an alloying element selected from tin, indium, gallium, or combinations thereof. A first fluid flow path is disposed through hollow tube from the tube inlet to the tube outlet. A second fluid flow path is disposed across an outer surface of the hollow tube through spaces between adjacent fins.

Abstract: A heat exchanger is disclosed. The heat exchanger includes a hollow tube extending from a tube inlet to a tube outlet. The hollow tube includes a wall that includes a core of a first aluminum alloy, and a cladding over the core of a second aluminum alloy. The second aluminum alloy is less noble than the first aluminum alloy and includes an alloying element selected from tin, indium, or gallium, or combinations thereof. A first fluid flow path is disposed along an inner surface of the wall from the tube inlet to the tube outlet, and a second fluid flow path is disposed across an outer surface of the wall.

Abstract: A personal heating ventilation and air conditioning system (HVAC) for an aircraft seat includes at least one aircraft seat, a heating/cooling device disposed on the at least one aircraft seat and at least one branch configured to provide at least one flow path from the heating/cooling device. The system also includes at least one sub-branch provided within the at least one aircraft seat. The at least one sub-branch is configured to provide flow from the at least one branch through the at least one aircraft seat. The system also includes means for expelling air from the at least one sub-branch to an interior surface of the at least one aircraft seat.

Abstract: A heat exchanger is disclosed. The heat exchanger includes a hollow tube extending from a tube inlet to a tube outlet. The hollow tube includes a wall inner surface comprising a copper alloy or a first aluminum alloy. A first fluid flow path is disposed along the wall inner surface from the tube inlet to the tube outlet. A turbulator is disposed within the hollow tube along the first fluid flow path, and the turbulator comprises a second aluminum alloy that is less noble than the copper or first aluminum alloy. A second fluid flow path is disposed across an outer surface of the wall.

Abstract: A compressor is disclosed, including an outer casing and a fluid guide around a cavity within the casing. An inlet is in operative fluid communication with the cavity, and an outlet is also in operative fluid communication with the cavity. A prime mover includes an actuator disposed in the cavity. The actuator includes a surface arranged to receive fluid in the cavity from the inlet, impart compression to received fluid in the cavity, and discharge compressed fluid to the outlet. A surface of the compressor includes a cladding of a second aluminum alloy over a core of a first aluminum alloy, wherein the second aluminum alloy is less noble than the first aluminum alloy and includes an alloying element selected from tin, indium, gallium, or combinations thereof.

Abstract: A carbon dioxide scrubber includes an adsorption chamber through which an adsorption airflow is directed, a regeneration chamber through which a regeneration airflow is directed, and a divider wall separating the adsorption chamber from the regeneration chamber. A carbon dioxide sorbent bed extends across the adsorption chamber and the regeneration chamber. The carbon dioxide sorbent bed is configured to adsorb carbon dioxide from the adsorption airflow into the sorbent bed and exhaust carbon dioxide from the carbon dioxide sorbent bed into the regeneration airflow. The carbon dioxide sorbent bed is continuously movable through the adsorption chamber and the regeneration chamber.

Abstract: An example SPR detection system includes a first prism having a first surface adjacent to a first metal layer exposed to a sample gas, and a second prism having a second surface adjacent to a second metal layer exposed to a reference gas. At least one light source is configured to provide respective beams to the first and second surfaces, where each of the beams causes SPR of a respective one of the metal layers. At least one photodetector is configured to measure a reflection property of reflections of the respective beams from the metal layers during the SPR. A controller is configured to determine whether a target gas is present in the sample gas based on a known composition of the reference gas and at least one of an electrical property of the first and second metal layers during the SPR and the reflection property of the metal layers.

Abstract: An aircraft environmental control system includes means for mixing and conditioning bleed air from a bleed air input and recirculation air from an aircraft interior to provide mixed, conditioned air to the aircraft interior. The system also includes a first contaminant removal device and a second contaminant removal device arranged in a path of at least part of the recirculation air, prior to the means for mixing and conditioning, and a valve (SV1) arranged to alternate flow of recirculation air through the first and second contaminant removal devices.

Abstract: An aircraft environmental control system includes means for mixing and conditioning bleed air from a bleed air input and recirculation air from an aircraft interior to provide mixed, conditioned air to the aircraft interior, the system further includes one or more rotating wheels arranged in a path of at least part of the recirculation air, prior to the means for mixing and conditioning, the one or more wheels configured to remove one or more contaminants and/or moisture from the recirculation air before mixing and conditioning.