Aircraft having multiple independent yaw authority mechanisms
An aircraft has multiple independent yaw authority mechanisms. The aircraft includes an airframe having first and second wings with at least first and second pylons extending therebetween and with a plurality of tail members extending therefrom each having an active control surface. A two-dimensional distributed thrust array is coupled to the airframe that includes a plurality of propulsion assemblies each having a rotor assembly and each operable for thrust vectoring. A flight control system is operable to independently control each of the propulsion assemblies. A first yaw authority mechanism includes differential speed control of rotor assemblies rotating clockwise compared to rotor assemblies rotating counterclockwise. A second yaw authority mechanism includes differential longitudinal control surface maneuvers of control surfaces of two symmetrically disposed tail members. A third yaw authority mechanism includes differential thrust vectoring of propulsion assemblies.
1. An aircraft operable for a thrust-borne flight mode and a wing-borne flight mode, the aircraft having multiple independent yaw authority mechanisms, the aircraft comprising:
an airframe having first and second wings with at least first and second pylons extending therebetween, each wing having at least two tail members extending therefrom with each tail member having an active control surface;
a pod assembly is coupled between the first and second pylons;
a two-dimensional distributed thrust array coupled to the airframe, the thrust array including a plurality of propulsion assemblies each having a rotor assembly and each operable for single-axis longitudinal thrust vectoring; and
a flight control system operable to independently control each of the propulsion assemblies;
wherein, in the thrust-borne flight mode, the first wing is forward of the pod assembly and the second wing is aft of the pod assembly;
wherein, in the wing-borne flight mode, the first wing is below the pod assembly and the second wing is above the pod assembly; and
wherein, in the thrust-borne flight mode, the aircraft has at least first, second and third yaw authority mechanisms, the first yaw authority mechanism including differential speed control of rotor assemblies rotating clockwise compared to rotor assemblies rotating counterclockwise, the second yaw authority mechanism including differential longitudinal control surface maneuvers of control surfaces of two symmetrically disposed tail members and the third yaw authority mechanism including differential longitudinal thrust vectoring of two symmetrically disposed propulsion assemblies.
2. The aircraft as recited in claim 1 wherein the differential speed control of rotor assemblies rotating clockwise compared to rotor assemblies rotating counterclockwise generates a torque imbalance in the aircraft which provides the first yaw authority mechanism.
3. The aircraft as recited in claim 1 wherein the differential longitudinal control surface maneuvers of control surfaces of two symmetrically disposed tail members generates a yaw moment for the aircraft which provides the second yaw authority mechanism.
4. The aircraft as recited in claim 1 wherein the differential longitudinal thrust vectoring of two symmetrically disposed propulsion assemblies generates a yaw moment for the aircraft which provides the third yaw authority mechanism.
5. The aircraft as recited in claim 1 wherein the differential speed control of rotor assemblies rotating clockwise compared to rotor assemblies rotating counterclockwise and the differential longitudinal control surface maneuvers of control surfaces of two symmetrically disposed tail members are used in combination as a fourth yaw authority mechanism.
6. The aircraft as recited in claim 1 wherein the differential speed control of rotor assemblies rotating clockwise compared to rotor assemblies rotating counterclockwise and the differential longitudinal thrust vectoring of two symmetrically disposed propulsion assemblies are used in combination as a fifth yaw authority mechanism.
7. The aircraft as recited in claim 1 wherein the differential longitudinal control surface maneuvers of control surfaces of two symmetrically disposed tail members and the differential longitudinal thrust vectoring of two symmetrically disposed propulsion assemblies are used in combination as a sixth yaw authority mechanism.
8. The aircraft as recited in claim 1 wherein the differential speed control of rotor assemblies rotating clockwise compared to rotor assemblies rotating counterclockwise, the differential longitudinal control surface maneuvers of control surfaces of two symmetrically disposed tail members and the differential longitudinal thrust vectoring of two symmetrically disposed propulsion assemblies are used in combination as a seventh yaw authority mechanism.
9. The aircraft as recited in claim 1 wherein each propulsion assembly further comprises a housing, a gimbal coupled to the housing and operable to tilt about a single axis and a propulsion system coupled to and operable to tilt with the gimbal, the propulsion system including an electric motor having an output drive and the rotor assembly having a plurality of rotor blades, the rotor assembly rotatable with the output drive of the electric motor in a rotational plane to generate thrust.