A flight control system includes a flight control computer operable in a flight state and a ground state. A high demand trim relief logic is operable by the flight control computer in the ground state. The high demand trim relief logic is configured to automatically modify the neutral position of a rotor when a command input to the flight control computer to control the rotor is near an allowable limit.

Rotor assemblies for aircraft are described that include a plurality of blades that are disposed vertically on a common axis along different horizontal planes. When the rotor assemblies are free-wheeling, the blades form a vertically stacked configuration, and when the rotor assembly is driven in rotation to generate lift, the blades bloom out from the vertically stacked configuration. At least one of the blades in the rotor assembly has a blade geometry that is different with respect to other blades such that when the blades are vertically stacked and free-wheeling, the collective shape of the blades is aerodynamic in shape, based on the different blade geometry, that reduces aerodynamic drag on the rotor assembly.

Rotor assemblies for aircraft are described that include a plurality of blades that are disposed vertically on a common axis along different horizontal planes. When the rotor assemblies are free-wheeling, the blades form a vertically stacked configuration, and when the rotor assembly is driven in rotation to generate lift, the blades bloom out from the vertically stacked configuration. At least one of the blades in the rotor assembly has a blade geometry that is different with respect to other blades such that when the blades are vertically stacked and free-wheeling, the collective shape of the blades is aerodynamic in shape, based on the different blade geometry, that reduces aerodynamic drag on the rotor assembly.

A method and system for vector limiting of a rotor control volume for a helicopter with one or more controllers configured to issue a displacement command during a flight maneuver and a computer operably connected to the one or more controllers and configured to receive signals with a processor indicative of a displacement command for a rotor during a flight maneuver; determine with the processor an origination point for a command vector in a reference frame; determine with the processor the command vector in the reference frame; determine with the processor a command radius for the command vector; compare with the processor the command radius with values of estimated command radii in a look-up table; and determine with the processor a control volume limited command in response to the comparing of the command radius with the estimated command radius.

A method and system for vector limiting of a rotor control volume for a helicopter with one or more controllers configured to issue a displacement command during a flight maneuver and a computer operably connected to the one or more controllers and configured to receive signals with a processor indicative of a displacement command for a rotor during a flight maneuver; determine with the processor an origination point for a command vector in a reference frame; determine with the processor the command vector in the reference frame; determine with the processor a command radius for the command vector; compare with the processor the command radius with values of estimated command radii in a look-up table; and determine with the processor a control volume limited command in response to the comparing of the command radius with the estimated command radius.

A linkage assembly configured for use on a rotor blade having a first section and a second section, the second section being configured to rotate about a blade fold axis between an aligned position and a rotated position relative to the first section is provided. The linkage assembly includes a bracket having a first portion rotatably coupled to the first section about the blade fold axis and a second portion mounted to the second section. A spacer assembly is positioned between the bracket and an adjacent wall of the second section. The overall thickness of the spacer assembly is adjustable to control a distance between the second section and the bracket to adjust the rotated position.

An air vehicle includes a flight computer, a fuselage, and two rotors mounted symmetrically with respect to the fuselage. Each of the two rotors includes a servo mechanism to tilt a respective rotor of the two rotors about two axes of the respective rotor. The flight computer is configured to send control parameters to each of the two rotors, the control parameters including a rotational speed, a first tilt angle about a first axis of the two axes of the respective rotor, and a second tilt angle about a second axis of the two axes of the respective rotor. A method for operating the air vehicle is also provided.

A bearing system includes an inboard bearing assembly and an outboard bearing assembly. The inboard bearing assembly includes an inboard fitting and an inboard race. The inboard fitting includes a plate with a convex mating surface and a first aperture formed through the plate for receiving a blade root of a rotor blade. The inboard race comprising a concave mating surface configured to receive the convex mating surface a second aperture formed the inboard race. The outboard bearing assembly includes an outboard bearing assembly comprising an outboard fitting having an aperture formed therethrough for receiving the blade root of the rotor blade.

A bearing system includes an inboard bearing assembly and an outboard bearing assembly. The inboard bearing assembly includes an inboard fitting and an inboard race. The inboard fitting includes a plate with a convex mating surface and a first aperture formed through the plate for receiving a blade root of a rotor blade. The inboard race comprising a concave mating surface configured to receive the convex mating surface a second aperture formed the inboard race. The outboard bearing assembly includes an outboard bearing assembly comprising an outboard fitting having an aperture formed therethrough for receiving the blade root of the rotor blade.

According to some embodiments, a rotorcraft includes a secondary rotor control system located proximate to the empennage of the rotorcraft. The secondary rotor control system includes at least one hydraulic pump and at least one hydraulic actuator. The at least one hydraulic pump is located proximate to the empennage. The at least one hydraulic actuator is located proximate to the empennage and configured to adjust at least one operating characteristic of the at least one secondary rotor blade.