This presentation will describe a method for testing an aircraft DC electrical power system in Cooling Margin Campaign flight test condition based on a Load Bank that provides artificial electrical load to an aircraft power source. The system performance and associated cooling capability is verified with electrical load bank integration under fully loaded maximum continuous load conditions. Cooling margin flight test campaign is performed in hot weather condition under high current capacity electrical load banks, 300A, both qualified to aircraft standards. Flight test regime is required to test and verify generator cooling duct performance to the systems fully electrical load capacitance. Auxiliary systems such as aircraft telemetry systems and FTE remote control capabilities provide real time health monitoring, helping flight safety hazards assessment.