US Patent 9889939 Environmental control system and methods of operating same

An environmental control system includes an air supply system coupled to an aircraft. The air supply system includes an external air supply device coupled to the aircraft and a supply duct coupled in flow communication to the external air supply device. An air supply outlet is coupled in flow communication to the supply duct and in flow communication with an occupancy zone and/or a floor distribution section. An air recirculation system is coupled to the floor distribution section. The air recirculation system includes a recirculation supply device coupled to the aircraft and a recirculation duct coupled in flow communication to the recirculated supply device and coupled to the floor distribution section. A recirculation outlet is coupled in flow communication to the recirculation duct and in flow communication with the recirculation zone and/or the floor distribution section.