Method of operating a rotorcraft in a single engine operation mode

A method of operating a rotorcraft flying in cruise mode, wherein the rotorcraft comprises a rotor with associated rotor actuators, two engines for powering the rotor, and a flight control system for controlling the rotor actuators, the method comprising:

• determining whether the rotorcraft is operating in an All Engines Operative mode wherein the two engines power the rotor, or in a Single Engine Operation mode wherein only a first engine of the two engines power the rotor while a second engine of the two engines is inactive;
• in response to determining that the rotorcraft is operated in the Single Engine Operation mode, monitoring the first engine to enable detection of engine failures;
• and
• if during monitoring of the first engine an engine failure of the first engine is detected, entering into autorotation of the rotor upon detection of the engine failure by adjusting the rotor actuators;
• wherein the method further comprises:
• adjusting a current rotor speed of the rotor to a predetermined autorotation rotor speed by re-adjusting the rotor actuators.

A method of operating a rotorcraft, wherein the rotorcraft comprises a main rotor with an associated main rotor actuator, two engines for powering the main rotor, and a flight control system for controlling the main rotor actuator, the method comprising:

• determining whether the rotorcraft is operated in an All Engines Operative mode wherein the two engines are powering the main rotor, or in a Single Engine Operation mode wherein only a first engine of the two engines is powering the main rotor while a second engine of the two engines is inactive;
• after determining that the rotorcraft is operated in the Single Engine Operation mode, monitoring the first engine powering the main rotor to enable detection of engine failures;
• and
• if during monitoring of the first engine an engine failure of the first engine is detected, emitting a visual and/or audible indication, and upon detection of the engine failure, adjusting the main rotor actuator to enter the main rotor into autorotation.