| 主权项 |
1. A method of stopping an engine of a rotorcraft in overspeed, the rotorcraft including at least one engine, the engine comprising a gas generator and a power assembly, the power assembly having at least one power turbine set in rotation by gas coming from the gas generator, the power assembly having at least one power shaft constrained to rotate with the power turbine, the power assembly being rotatable about a longitudinal axis at a speed referred to as the “speed of rotation (N2)”;
wherein: prior to a flight, a relationship is determined that provides a time derivative of the speed of rotation referred to as a time “limit derivative”, over at least one range of speeds of rotation, the limit derivative according to the relationship being a function of the speed of rotation and varying as a function of the speed of rotation; and wherein during a flight:
the speed of rotation reached by the power assembly is measured, and referred to as the “current” speed;the time derivative of the speed of rotation is determined, and referred to as the “current” derivative; andwhen the current speed is located in a said range specified by the relationship, the engine is stopped automatically when the limit derivative corresponding to the current speed in application of the relationship is less than or equal to the current derivative. |
