US Patent 7857257 Aircraft thermal management system with reduced exhaust re-ingestion

A thermal management system includes a cooling duct system that locates a ram air intake and an exhaust through a first aircraft surface above a second aircraft surface which locates a fan intake. During ground operations, an anti-re-ingestion door is open and a ram air door is closed such that the fan system may draw relatively cooler air from below the aircraft and exhaust the heated air above the aircraft to minimize re-ingestion of the heated exhaust. During flight operations, the anti-re-ingestion door is closed and the ram air door is open such that ram airflow communicates through the fan system prior to communication through the heat exchanger. Both the anti-re-ingestion door and the ram air door may also be operated in flight.