Engine with hybrid powertrain and corresponding control method

The invention relates to an engine (100) provided with a powertrain which comprises a heat engine (1) and an output shaft (A1), an electric motor (2), a battery (40) for supplying the electric motor (2) and a propeller propulsion system comprising a propeller (3) and a propeller shaft (A3), referred to as shaft, to which the propeller (3) is coupled. The powertrain further comprises a system of clutches (E123, E14, E23, E324) designed for different configurations that make it possible to selectively drive the propeller by means of the heat engine without transmission of the rotation of the electric motor to the propeller; to drive the propeller by means of the electric motor without transmission of the rotation of the heat engine to the propeller; to drive the propeller by means of combined transmission of the rotation of the heat engine and the rotation of the electric motor to the propeller. The electric motor comprises a stator and a rotor mounted for rotation about a shaft that is rigidly connected, or can be coupled, to the propeller shaft. The invention further relates to a corresponding control method.