Method and configuration for an auxiliary power engine to deliver propulsive and/or non-propulsive energy in a helicopter architecture

A method for supplying propulsive and/or non-propulsive power in a helicopter architecture including an on-board power supply network, a main traction system coupled to a mechanical transmission system which drives propulsion members during flight, a conversion of mechanical energy into electrical energy coupled to the mechanical transmission system and/or to the main traction system providing non-propulsive power to the on-board power supply network, the method comprising:

• coupling, by energy conversion, an additional auxiliary engine to the on-board network, to provide the engine, on ground, with non-propulsive power, and to the main traction system for its start-up and to be able to provide, during flight, non-propulsive power to the on-board network, in addition to and ultimately instead of drawing-off carried out on the mechanical transmission system and/or the main traction system,
• the auxiliary engine further configured to provide electrical energy to a dedicated traction system on the mechanical transmission system to increase or partially provide the propulsive power.