An aircraft system for improved cooling efficiency comprises at least one air conditioning pack, coupled to an aircraft, having at least one air compression device powered by at least one power source and having an air compression device inlet. The system further comprises at least one air flow path for redirecting a first portion of a first volume of aircraft interior outflow air from an aircraft interior to the air compression device inlet. The air flow path includes a shutoff valve to enable the air flow path during ground operation of the aircraft and to disable the air flow path for flight operation of the aircraft. The air compression inlet mixes the first volume of aircraft interior outflow air with a second volume of aircraft exterior inflow air to form an air mixture. The air conditioning pack conditions and circulates the air mixture into the aircraft interior.