A propulsion system (50, 350) for an aircraft, the propulsion system (50, 350) comprising: a combustion engine; an electric generator (56, 354) mechanically driven by the combustion engine, the electric generator (56, 354) configured to generate alternating current electrical power; a power bus (58, 356) electrically connected to the electric generator (56, 354) and configured to receive and transmit the alternating current electrical power generated by the electric generator (56, 354); an electric propulsor assembly comprising an electric motor and a propulsor drivingly connected to the electric motor, the electric motor electrically coupled to the power bus (58, 356) for the receiving alternating current electrical power from the power bus (58, 356), at least one of the power bus (58, 356) or the electric propulsor assembly comprising a resistor selectively connectable, via a switch, in series with the electric motor of the electric propulsor assembly for limiting a current provided to the electric motor; and a controller configured to determine a rotational speed of the electric generator (56, 354) and a rotational speed of the electric motor, characterized in that: the controller is operable to cause the switch to move to a first position to connect the resistor in series with the electric motor when the rotational speed of the electric motor is below a predetermined threshold of the rotational speed of the electric generator (56, 354), and to a second position to bypass the resistor when the rotational speed of the electric motor is above the predetermined threshold of the rotational speed of the electric generator (56, 354). a combustion engine; an electric generator (56, 354) mechanically driven by the combustion engine, the electric generator (56, 354) configured to generate alternating current electrical power; a power bus (58, 356) electrically connected to the electric generator (56, 354) and configured to receive and transmit the alternating current electrical power generated by the electric generator (56, 354); an electric propulsor assembly comprising an electric motor and a propulsor drivingly connected to the electric motor, the electric motor electrically coupled to the power bus (58, 356) for the receiving alternating current electrical power from the power bus (58, 356), at least one of the power bus (58, 356) or the electric propulsor assembly comprising a resistor selectively connectable, via a switch, in series with the electric motor of the electric propulsor assembly for limiting a current provided to the electric motor; and a controller configured to determine a rotational speed of the electric generator (56, 354) and a rotational speed of the electric motor, characterized in that: the controller is operable to cause the switch to move to a first position to connect the resistor in series with the electric motor when the rotational speed of the electric motor is below a predetermined threshold of the rotational speed of the electric generator (56, 354), and to a second position to bypass the resistor when the rotational speed of the electric motor is above the predetermined threshold of the rotational speed of the electric generator (56, 354).