US Patent 6883335 Air conditioning system

An air conditioning system for an aircraft in which cabin air is recirculated and mixed with cold air from an air conditioning machine which includes at least one expansion turbine over which warm pressurized air is expanded and cooled, and wherein the system includes a heat exchanger in which a heat load from hot cabin air is exchanged with the warm pressurized air prior to the pressurized air being expanded by the expansion turbine, further including a condenser heat exchanger in which recirculating cabin air is used to cool and promote water removal from the warm pressurized air before it is expanded by the expansion turbine.