The present invention includes a span-balance pocket in a surface of a rotor blade, the span-balance pocket including an inboard surface and an outboard surface; and one or more weights disposed in the span-balance pocket to span-balance the rotor blade; and at least one of one or more retention devices to retain the one or more weights against the outboard surface of the span-balance pocket or the span-balance pocket is machined or molded into a tip block of the rotor blade.

A main rotor blade assembly for a rotary wing aircraft is provided including a main rotor blade root region, a main rotor blade inboard region arranged outboard of said main rotor blade root region, a main rotor blade main region arranged outboard of said main rotor blade inboard region, and a main rotor blade tip region arranged outboard of said main rotor blade main region. At least one of chord, twist, sweep, airfoil shape, and thickness/chord of the main rotor blade assembly has been optimized to achieve balanced high speed forward flight and hover relative to both efficiency and high thrust capability.

A helicopter has a mast axis and a rotorcraft blade assembly. The rotorcraft blade assembly has a main body and a blade tip movable relative to the main body. The rotorcraft blade assembly is selectively rotatable about the mast axis.

The present invention includes a first barrier layer configured to cover a leading edge of the blade or wing; one or more electrical bus bars disposed on the first barrier layer proximate to and substantially parallel with the leading edge; a ground bus bar disposed on the first barrier layer proximate to and substantially parallel with the leading edge; a second barrier layer disposed over the one or more electrical bus bars and the ground bus bar; one or more heating elements disposed on the second barrier layer, and each heating element electrically connected to one of the electrical bus bars and to the ground bus bar; and a third barrier layer disposed over the one or more heating elements.

A tiltrotor aircraft is designed to accommodate rotors of different diameters, as well as corresponding wings and fuselages with different span and length, while maintaining very high parts commonality, especially with respect to drive train and power source. This enables design and operation of a fleet of such aircraft with significantly different rotor diameters, which are nevertheless optimized for different missions. In preferred embodiments the rotors are configured to have high stiffness and low weight to reduce aero-structural dynamic issues across the fleet. Also in preferred embodiments drive systems are designed for a full range of speed, torque, and power associated with all intended rotors. Turboshaft engine speeds are restricted to a narrow RPM range, so that a single gearset can be replaced to achieve the desired rotor RPM. Also in preferred embodiments, aircraft in a fleet can differ in folded length, empty weight, payload length by up 50%.

A biplaner rotor blade has an upper airfoil section connected to a lower airfoil section such that the upper airfoil and lower airfoil are rotated in separate planesan upper plane and a lower plane. The upper airfoil has a root end attached to a hub at an upper location of the hub and the lower airfoil has a root end attached to the hub at a lower location of the hub. The upper airfoil converges with the lower airfoil to form a blade tip end at the outermost portion of the blade, thus generating lift along two geometric planes.

A rotor, in particular for aircraft and wind turbines, includes a driven, rotatably mounted rotor head and rotor blades protruding from the rotor head, and having a profiled cross-section. A device for mechanically breaking up pieces of ice formed on the rotor blade is attached or formed on at least one rotor blade.

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 helicopter rotor device with a mechanical means for configuring rotor tips in order to control dust of brown outs or the method to accomplish the reduction or elimination of the brownout dust.

A gas turbine engine for an aircraft, includes: an engine core having a turbine, a compressor, and a core shaft connecting the turbine to the compressor; a fan assembly located upstream of the engine core; and a gearbox receiving an input from the core shaft and outputs drive to the fan assembly so as to drive the fan assembly at a lower rotational speed than the core shaft, wherein the fan assembly has fan blades mounted around a hub, the fan blades having blade tips defining an outer diameter of the fan assembly of from around 220 cm to around 400 cm, the hub having slots located around a rim of the hub, each slot receiving a root of a corresponding fan blade, wherein a ratio of a mass of the hub to a total mass of the fan blades is within the range of around 0.45 to around 0.7.