A rotor for a hover-capable aircraft is described that comprises: a hub rotatable about a first axis and at least two blades hinged to the hub; each blade comprises a main portion hinged to the hub and a tip portion, which is arranged radially outermost with respect to first axis with respect to the corresponding main portion; the tip portion of each blade is movable with respect to the corresponding main portion of that blade; the tip portion of each blade is selectively movable with respect to the corresponding main portion of that blade between a first position, in which it defines a dihedral or anhedral angle with respect to the corresponding main portion; and a second position, in which it defines a positive or negative sweep angle with respect to the corresponding main portion.

In one aspect, the present disclosure provides a system for reducing vibrations or stresses in a rotor blade system. The system may include at least three rotor blades configured to be rotated about a main rotor axis, where each of the three rotor blades may be adjusted by at least one electrically-adjustable control rod of a plurality of control rods. The plurality of control rods may include a first number of control rods forming a first group, and the plurality of control rods may include a second number of control rods forming a second group. A first circuit for may activate or deactivate the first group of control rods, and a second circuit may activate or deactivate the second group of control rods.

In one aspect, the present disclosure provides a system for reducing vibrations or stresses in a rotor blade system. The system may include at least three rotor blades configured to be rotated about a main rotor axis, where each of the three rotor blades may be adjusted by at least one electrically-adjustable control rod of a plurality of control rods. The plurality of control rods may include a first number of control rods forming a first group, and the plurality of control rods may include a second number of control rods forming a second group. A first circuit for may activate or deactivate the first group of control rods, and a second circuit may activate or deactivate the second group of control rods.

A bond fixture includes a support structure and a first assembly coupled to the support structure. The first assembly includes a frame defining a chamber and a first pressure pad and second pressure pad coupled to the frame opposite one another and positioned within the chamber. The second pressure pad is movable to control a pressure applied by the first pressure pad and the second pressure pad.

A bond fixture includes a support structure and a first assembly coupled to the support structure. The first assembly includes a frame defining a chamber and a first pressure pad and second pressure pad coupled to the frame opposite one another and positioned within the chamber. The second pressure pad is movable to control a pressure applied by the first pressure pad and the second pressure pad.

A rotor blade disassembly method includes applying spanwise support to a rotor blade body and heating a bond disposed on an end of the rotor blade body. The method also includes removing the spanwise support from the rotor blade body and exerting shear stress on the bond using weight of the rotor blade body. A blade disassembly system is also described.

A rotor blade disassembly method includes applying spanwise support to a rotor blade body and heating a bond disposed on an end of the rotor blade body. The method also includes removing the spanwise support from the rotor blade body and exerting shear stress on the bond using weight of the rotor blade body. A blade disassembly system is also described.

The blade support apparatus relates to capturing and stabilizing airfoils such as helicopter blades to enable ground transport without requiring removal of airfoils or blades with the blade support apparatus and blades in a protective container. The blade support apparatus captures and stabilizes helicopter blades utilizing a support frame with vertical and radial adjustable supports. These supports have contoured padded cradles and means of adjusting the height and angle of the cradles to match the profile being captured. The blade support apparatus enables loading, transport, and unloading of the airfoils for transport in a separate blade container which may either be stand alone or attaches to a helicopter transport apparatus. An alternate embodiment utilizes a support frame which is vertically and radially adjustable. Within the support frame are the same contoured padded swivel cradles which also adjust to the height and angle of the profile being captured.

An aerial vehicle is provided including rotor units connected to the aerial vehicle, and a control system configured to operate at least one of the rotor units. The rotor unit includes rotor blades, wherein each rotor blade includes a surface area, and wherein an asymmetric parameter is defined, at least in part, by the relationship between the surface areas of the rotor blades. The value of the asymmetric parameter is selected such that the operation of the rotor unit: (i) moves the rotor blades such that each rotor blade produces a respective vortex and (ii) the respective vortices cause the rotor unit to produce a sound output having an energy distribution defined, at least in part, by a set of frequencies, wherein the set of frequencies includes a fundamental frequency, one or more harmonic frequencies, and one or more non-harmonic frequencies having a respective strength greater than a threshold strength.

A rotor for a hover-capable aircraft includes a hub rotatable about a first axis and at least two blades hinged to the hub. Each blade has a main portion hinged to the hub and a tip portion, which is arranged radially outermost with respect to first axis with respect to the corresponding main portion. The tip portion of each blade is movable with respect to the corresponding main portion of that blade. The tip portion of each blade is selectively movable with respect to the corresponding main portion of that blade between a first position, in which it defines a dihedral or anhedral angle with respect to the corresponding main portion; and a second position, in which it defines a positive or negative sweep angle with respect to the corresponding main portion.