Start clutch control method for piston engine of unmanned helicopter

The invention provides a start clutch control method for a piston engine of an unmanned helicopter, and belongs to the technical field of engine control. The method includes the steps that when the engine speed is controlled to reach a preset value, an alternator is switched on; then, a clutch is arranged at a connecting position to reduce the engine speed; whether the reduction rate of the enginespeed is greater than a specified value or not is judged, if yes, the alternator is switched on again after the clutch is at a holding position for a period of time, and the operation is repeatedly executed until the reduction rate of the engine speed is not greater than the specified value; finally, the above steps are repeatedly executed until the rotor speed and the engine speed are consistent, and the clutch is arranged at the holding position. By means of the method, the combination of unmanned automatic start control and clutch control over the double-cylinder piston engine is realized,the capability of manual