Gyroplane

An improved gyroplane having variable pitch rotor with plural blades, a forward thrust means, a wing, a horizontal stabilizer, and an engine to rotate the rotor, the improvement comprising:

• the rotor having an edgewise stiffness of at least 80,000 pounds inch.sup.2 per pound of aircraft gross weight and blade weights to enable rotation at a speed to store a minimum of 100 foot pounds per pound of gross weight;
• the engine being adapted to rotate the rotor at said speed;
• flight control means to set the rotor blade angle of attack to a minimum lift condition;
• said flight control means being adapted for changing the angle of attack of the rotor blades to a lift condition for vertical climbing;
• means to increase thrust to achieve an increasing horizontal velocity necessary to maintain a selected altitude, first with the rotor providing most of the lift and until the wing provides most of the lift;
• said flight control means also being adapted to reduce the pitch of the rotor disc and angle of attack of the rotor blades to essentially zero lift to decrease the rotor rotational speed to minimize drag during horizontal flight.

An improved gyroplane having a rotor with variable pitch rotor blades, a forward thrust means, a wing, a horizontal stabilizer, and an engine to rotate the rotor, the improvement comprising:

• the rotor having a construction and a weight to enable rotation at a speed to store a minimum of 100 foot pounds of kinetic energy per pound of gross weight;
• the engine being adapted to rotate the rotor at said speed;
• flight control apparatus to set the rotor blade pitch to a minimum lift condition;
• said flight control apparatus being adapted for changing the angle of attack of the rotor blades to a lift condition for vertical climbing;
• an engine speed controller to increase engine speed and thrust of forward thrust means to achieve an increasing horizontal velocity necessary to maintain a selected altitude, first with the rotor providing most of the lift and until the wing provides most of the lift;
• said flight control apparatus also being adapted to reduce the pitch of the rotor disc and angle of attack of the rotor blades to essentially zero lift to decrease the rotor rotational speed to minimize drag during horizontal flight.

A method of controlling a gyroplane during substantially rotor unloaded flight, comprising:

• providing an aerodynamic pitch control surface that is pivotable relative to the fuselage of said gyroplane;
• providing a rotor that rotates to define a rotor disc that is pivotable relative to the fuselage of said gyroplane for tilting the rotor disc;
• providing pilot control means for simultaneously controlling the angle of the pitch control surface and the tilt of the rotor disc relative to the fuselage of the gyroplane;
• controlling the angle of the pitch control surface and the tilt of the rotor disc with the pilot control means so that the pitch control surface and the rotor disc move in the same angular direction and in direct proportion to each other.

A method of controlling a gyroplane comprising the steps of:

• providing an aerodynamic pitch control surface that is pivotable relative to the fuselage of said gyroplane;
• providing a rotor that rotates to define a rotor disc that is pivotable relative to the fuselage of said gyroplane;
• providing pilot control means for simultaneously controlling the angle of the pitch control surface and the tilt of the rotor disc relative to the fuselage of the gyroplane;
• and
• during substantially rotor unloaded flight, controlling the angle of the pitch control surface and the angle of the rotor disc using the pilot control means so that the pitch control surface and the rotor disc move in the same angular direction and in direct proportion to each other;
• and
• during substantially rotor loaded flight, maintaining a generally fixed angle of the pitch control surface relative to the fuselage of the gyroplane.