Bearing cooling flow for turbine and compressor utilized to supply air for aircraft cabin

A system comprising:

• an environmental control system configured to supply air to an aircraft cabin and including a machine and a heat exchanger;
• the machine having a turbine with a turbine impeller and a turbine inlet configured to port compressed air to said turbine impeller;
• a compressor impeller and compressor inlet configured to port air to said compressor impeller, said compressor impeller connected to deliver air into a compressor outlet, said compressor outlet connected to said turbine inlet, a turbine outlet connected to a first connection connected to the heat exchanger, said heat exchanger to be connected to the aircraft cabin;
• a drive shaft connecting said turbine impeller to said compressor impeller;
• said drive shaft including a radially outwardly extending thrust disk, and thrust bearings provided on each of two axial faces of said thrust disk;
• and
• a cooling air inlet connected to pass air along said thrust bearings, and radially inwardly and axially along said drive shaft, and then to a cooling air outlet, said cooling air outlet connected to a second connection maintained separate from said first connection;
• wherein said second connection is connected to a dump at atmospheric pressure;
• and
• wherein holes pass through said compressor impeller, such that air from said compressor inlet is connected to pass to the cooling air outlet.