Patent ID: 7607318

Claim:
An integrated environmental control system for an aircraft compartment and aircraft power system, comprising: first and second air compressors, each air compressor adapted to receive and compress airflow from the aircraft exterior; an auxiliary power unit comprising: a first shaft, a power turbine rotatably mounted on the first shaft, a third air compressor rotatably mounted on the first shaft and adapted to receive and compress airflow from the aircraft exterior, and a first cooling turbine rotatably mounted on the first shaft and adapted to cool the airflow; and first and second environmental control systems, each environmental control system comprising: a first heat exchanger adapted to receive the airflow from the first, second, and third air compressors and to forward airflow to the aircraft compartment, a recycling heat exchanger adapted to receive airflow from the aircraft compartment and to recirculate the airflow back to the aircraft compartment, a second shaft, a fourth compressor rotatably mounted on the second shaft for compressing the airflow, and a second cooling turbine rotatably mounted on the second shaft for expanding and cooling the airflow.