A system on an aircraft that eliminates hot-swapping of circuit boards to prevent damage to the circuit board connector interfaces. The system supplies power to a circuit card only when there is an effective coupling between a circuit card connector and an opposite mating connector. A power control circuit responds to a card present signal which indicates when the circuit card connector is coupled to the opposite mating connector. A logic circuit converts the card present signal to a power supply enable signal. A main power supply receives the power supply enable signal and provides power to the circuit card only when the circuit card connector and the opposite mating connector are appropriately coupled.