Abstract: A control system prevents electrical overloads in an aircraft of the type in which electrical loads are automatically connected to an electrical supply bus when the wing flaps are extended. The control system determines the maximum capability of the electrical generators for generating electricity and determines the wing flap position. Because electrical load is related to the wing flap position in this type of aircraft, the control system automatically correlates the wing flap position to electrical load. The control system operatively disconnects electrical load from the supply bus, or prevents energization of additional electrical load, when it determines that the maximum power generating capacity of the operative electrical generators will be exceeded by the automatic connection of the electrical load upon extension of the wing flaps.A test circuit apparatus is used for checking proper operation of the control system.