Abstract: Drive system for an aircraft, including: a propeller; electric motor; transmission system for transmitting positive torque from the motor to drive the propeller and negative torque from the propeller in windmill braking state to drive the motor; interface for inputting an input; first unit for controlling torque acting on the motor; second unit for detecting rotational speed of the motor; selection unit to select an active mode from propulsion mode and recovery mode, wherein the motor generates recovery energy in the recovery mode; and management system to control energy flow in an electrical system of the aircraft, the electrical system including the motor, is controlled according to the active mode; wherein the selection unit is configured to select the active mode according to the input, rotational speed, and predefined envelope, wherein the envelope indicates a maximum positive torque and minimum negative torque that depends on the rotational speed.

Abstract: Drive system for an aircraft, including: a propeller; electric motor; transmission system for transmitting positive torque from the motor to drive the propeller and negative torque from the propeller in windmill braking state to drive the motor; interface for inputting an input; first unit for controlling torque acting on the motor; second unit for detecting rotational speed of the motor; selection unit to select an active mode from propulsion mode and recovery mode, wherein the motor generates recovery energy in the recovery mode; and management system to control energy flow in an electrical system of the aircraft, the electrical system including the motor, is controlled according to the active mode; wherein the selection unit is configured to select the active mode according to the input, rotational speed, and predefined envelope, wherein the envelope indicates a maximum positive torque and minimum negative torque that depends on the rotational speed.