A convertible aircraft system is provided that can convert to a helicopter configuration, an airplane configuration, or a gyroplane configuration before, during, or after flight. The convertible aircraft system includes a fuselage, a proximal flight assembly, a distal flight assembly, a support spar, and a tail assembly. The fuselage is the main structural body of the present invention. The proximal flight assembly and the distal flight assembly are the flight system of the present invention. The support spar provides an axis of rotation and a pole support for the proximal flight assembly and the distal flight assembly. The tail assembly provides stability during flight of the present invention. In more detail, the tail assembly may comprise at least one vertical stabilizer, at least one horizontal stabilizer, and at least one rudder in order to provide stability during flight of the present invention.

A method for equalizing rolling moments at high advance ratios is disclosed including impelling an aircraft in a forward direction at an airspeed by means of a thrust source and rotating a rotor of the aircraft at an angular velocity with respect to the airspeed effective to cause a positive total lift on each blade due to air flow over the blades in the retreating direction when the blade is moving in the retreating direction. The rotor includes an even number of blades placed at equal angular intervals around the rotor hub. One or both of cyclic pitch and rotor angle of attack are adjusted such that a rolling moment of the retreating blade due to reverse air flow is between 0.3 and 0.7 times a rolling moment on the advancing blade due to lift.

In one aspect, a rotor assembly includes a hub and a plurality of rotor blades; at least one blade root actuator configured to adjust at least one of the plurality of rotor blades independently of the other rotor blades to accommodate forces on the aircraft; and at least one controller couplable to the at least one blade root actuator and configured to send signals to the at least one blade root actuator to enable adjustment of the at least one of the plurality of rotor blades. In another embodiment, at least one blade flap is associated with a rotor blade can be actuated to adjust the shape of the rotor blade. In some embodiments, there are methods and systems incorporating at least one of the root blade actuator and the blade flap for stabilizing a tiltrotor aircraft by counteracting destabilizing forces on at least one rotor blade.

A method for equalizing rolling moments at high advance ratios is disclosed including impelling an aircraft in a forward direction at an airspeed by means of a thrust source and rotating a rotor of the aircraft at an angular velocity with respect to the airspeed effective to cause a positive total lift on each blade due to air flow over the blades in the retreating direction when the blade is moving in the retreating direction. The rotor includes an even number of blades placed at equal angular intervals around the rotor hub. One or both of cyclic pitch and rotor angle of attack are adjusted such that a rolling moment of the retreating blade due to reverse air flow is between 0.3 and 0.7 times a rolling moment on the advancing blade due to lift.

A VTOL rotor assembly for a compound VTOL aircraft, the VTOL rotor assembly having a rotor sleeve, a pair of rotor blades which are extendable from the rotor sleeve for vertical take off and landing and retractable to the rotor sleeve as forward air speed exceeds the stall speed for the compound VTOL aircraft, and a rotor hub for connecting the rotor sleeve to a rotor power assembly. Rotor blade motivators controlled by a rotor blade controller determine the pitch of the respective rotor blades through interaction of the pilot of the VTOL aircraft with the rotor blade controller.

A method for equalizing rolling moments at high advance ratios is disclosed including impelling an aircraft in a forward direction at an airspeed by means of a thrust source and rotating a rotor of the aircraft at an angular velocity with respect to the airspeed effective to cause a positive total lift on each blade due to air flow over the blades in the retreating direction when the blade is moving in the retreating direction. The rotor includes an even number of blades placed at equal angular intervals around the rotor hub. One or both of cyclic pitch and rotor angle of attack are adjusted such that a rolling moment of the retreating blade due to reverse air flow is between 0.3 and 0.7 times a rolling moment on the advancing blade due to lift.