Vapor compression cycle environmental control system

An environmental control system for use on an aircraft comprising:

• a first subsystem for providing power to an aircraft mounted accessory drive;
• said first subsystem comprising a power transmission means connected to said aircraft mounted accessory drive and a shaft for delivering power from said engine;
• a second subsystem for supplying pressurized ram air at a desired temperature to at least one of a flight deck and a cabin;
• and
• said second subsystem including a vapor compression cycle loop for removing energy from the ram air prior to said ram air being supplied to the at least one of said flight deck and said cabin.

A method for controlling the environment of an aircraft comprising the steps of:

• providing power from an engine onboard said aircraft to an aircraft mounted accessory drive;
• said power providing step comprising providing an air turbine connected to said aircraft mounted accessory drive and supplying bleed air from said engine to an inlet of said air turbine;
• supplying pressurized ram air at a desired temperature to at least one of a flight deck and a cabin;
• providing a vapor compression cycle loop;
• and
• removing energy from said ram air using said vapor compression cycle loop prior to supplying said ram air to the at least one of said flight deck and said cabin.