Patent ID: 7918415
Filing Date: 2011-04-05
Classification: B64C

Abstract:
1. Operating method for a convertible aircraft ( 1 ), equipped with a fuselage ( 2 ), standard fixed wings ( 3 ) with ailerons, a tail unit ( 4 ) with rudders ( 20 ), propulsion engines ( 5 ), a rotor ( 6 ) with blades ( 7 , 8 ) located at approximately the center of the fuselage in between the wings, a transmission between the engines and the rotor equipped with a brake and a clutch, and a landing gear ( 9 ), the method comprises direct and reverse transitions from a helicopter mode to an autogyro mode and from an autogyro-helicopter mode to an aeroplane mode, the direct transition from the helicopter mode to the autogyro mode comprising the following step: declutching the rotor from the propulsion engines; the direct transition from the autogyro-helicopter mode to the aeroplane mode comprising the following steps: adjusting the collective and cyclic pitches of the blades ( quickly reducing the rotational velocity of the rotor ( stopping the rotor in a transverse position of at least two of its blades ( retracting the rotor blades towards a stern of the aircraft, until their longitudinal axes are parallel to the fuselage ( rotating the blade which had a reverse air flow when the blades were stopped transversely to the direction of the flight to approximately 180° on its pitch axis; deploying the rotating blades, independently from one another, to an azimuthal position determined by a pre-determined range of angles; adjusting the angle of attack of the deployed blades until the blades are deployed in a position parallel to the fixed wings; and the reverse of each of these transitions accomplished by executing each of the above steps in reverse sequence.