PROTECTION FUNCTIONS

A method includes controlling an electric motor (104) of a hybrid-electric powerplant (106) for an aircraft using an EPC (electric powertrain controller) (120) and controlling a heat engine (102) of the hybrid-electric powerplant using an ECU (engine control unit) (114). The method includes protecting the hybrid-electric powerplant using the ECU to power down the electric motor, and/or using the EPC to power down the heat engine.