Sikorsky Aircraft Corporation

Lockheed Martin Corporation

United Technologies Corporation

General Dynamics Advanced Information Systems, Inc.

General Dynamics Advanced Technology Systems, Inc.

Peter F Lorber

Brian Ernest Wake

Robert C Moffitt

Michael S Torok

Patrick Ormande Bowles

Byung-Young Min

William Arthur Welsh

Charles R Berezin

Blake Almy Moffitt

Geoffrey C R Davis

Andreas P F Bernhard

Antonios N Kotoulas

Margaret G Battisti

Anton J Landgrebe

Justin J Thomas

Wesley K Lord

David H Hunter

Steven D Weiner

Fred W Kohlhepp

Ray-Sing Lin

Robert D Beatty

Steven A Lozyniak

Lee A Hoffman

T Alan Egolf

Thomas Alan Egolf

Peter J Germanowski

Colman D Shattuck

Shawn Westfall

Nicholas Charles Tuozzo

Robert Morton

Richard B Ferraro

Colin Kemater Bunting

Nick Tuozzo

Colman D Schattuck

A rotor assembly including a fixed fairing including an interface portion and a hub fairing including a depression. The depression is configured to receive at least a portion of the interface portion. The hub fairing is rotatable relative to the fixed fairing.

Aerodynamic rotary interface

A rotary wing aircraft and a rotor assembly of a rotary wind aircraft is disclosed. The rotary wing aircraft includes at least one engine, and the rotor assembly is coupled to the at least one engine. The rotor assembly includes a first rotor hub, a second rotor hub, and a shaft fairing between the first rotor hub to the second rotor hub, the shaft fairing defined by a chord that varies between the first rotor hub and the second rotor hub.

Low drag sail fairing for coaxial rotor

A rotor assembly includes a first rotor hub and a second rotor hub. The second rotor hub is coupled to the first rotor hub via a shaft fairing. The first rotor hub has a flat first surface coupled to the shaft fairing and a curved second surface opposite the flat first surface. The second rotor hub has a flat first surface on the lower side and a curved second surface opposite the flat first surface.

Low drag hub for rotor

A rotorcraft is provided and includes a fuselage. The fuselage includes drag generating portions, a main rotor assembly and an auxiliary propulsor having an expected propulsion efficiency. The auxiliary propulsor is disposed to ingest boundary layer flows and in wake regions associated with the drag generating portions and is provided with a corresponding increase in the expected propulsion efficiency thereof.

Rotorcraft including auxiliary propulsor positioned to ingest boundary layer flow

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.

Dual rotor, rotary wing aircraft

A propulsor system for a rotary winged aircraft includes a propeller including having a propeller hub rotatable about a propeller axis and a plurality of propeller blades secured to and extending radially outwardly from the propeller hub. The propeller is oriented on the rotary winged aircraft to provide forward thrust for the rotary winged aircraft when the propeller is rotated about the propeller hub. A plurality of guide vanes non rotatable about the propeller axis are positioned upstream of the plurality of propeller blades. The plurality of guide vanes are positioned to turn an airflow flowing into the plurality or propeller blades, thereby reducing an angle of attack of the plurality of propeller blades relative to the airflow.

Guide vanes for a pusher propeller for rotary wing aircraft

A leading edge slat for multi-element rotor blade applications which provide multiple benefits and provide design direction which has heretofore been unexplored.

Leading edge slat airfoil for multi-element rotor blade airfoils

A multi-element rotor blade includes a main element and an active slat movable relative to the main element. The slat rotates and translates relative to the main element from a base position. The base position provides a compromise between minimum coefficient of drag C and maximum coefficient of lift C . In the advancing blade, since the airspeed thereof is significantly greater than the retreating blade, the slat is positively rotated from the base position to minimizes drag at low angles of attack. In the retreating blade, since the airspeed thereof is significantly lower than the advancing blade, the slat is negatively rotated and translated to maximize the coefficient of lift C .

Active control of multi-element rotor blade airfoils

Two neural networks are used to control adaptively a vibration and noise-producing plant. The first neural network, the emulator, models the complex, nonlinear output of the plant with respect to certain controls and stimuli applied to the plant. The second neural network, the controller, calculates a control signal which affects the vibration and noise producing characteristics of the plant. By using the emulator model to calculate the nonlinear plant gradient, the controller matrix coefficients can be adapted by backpropagation of the plant gradient to produce a control signal which results in the minimum vibration and noise possible, given the current operating characteristics of the plant.

Neural net controller for noise and vibration reduction

An elastomeric coupler assembly having a helical elastomeric bearing movably supports an active slat relative to a main element. An inner elastomeric coupler assembly and an outer elastomeric coupler assembly support the slat therebetween. Centrifugal force operates to drive the slat to a first position and an actuator rod operates in tension to pull upon the inner elastomeric coupler assembly to drive the slat in opposition to the centrifugal force to a second position. The helical elastomeric bearing is layered such that it defines a section of a circular helix. The circular helix provides a coupling, which converts a linear input parallel to a virtual hinge axis into a rotary output to pitch the slat. In operation, centrifugal force operates to slide the slat outboard toward the blade tip such that the attached slat moves elastomerically along the helical arc of the helical elastomeric bearing to rotate the slat nose down. To retract the slat, the actuator operates to place the actuator rod under tension to pull upon the active member and retract the slat in opposition to centrifugal force.

Directional elastomeric coupler

Blades, including helicopter rotor blades, gas turbine engine fan blades, air moving machinery fan blades, and the like, have an air inlet near the hub of the blade, which may be on the pressure side of the blade and/or near the leading edge or trailing edge nearer the tip of the blades, with an air plenum between the air inlet and the slots, whereby air is forced into the inlet, through the plenum and out of the slots into the flow adjacent the blades. The slots may be through the suction surface of the blade, typically near the boundary layer separation point, so that air flowing out of the slots into the boundary layer of the suction surface of the blade, thereby delay or prevent the onset of boundary layer separation, or to reduce supersonic shock. The inlet may be near the trailing edge of the blade, near the root, adjacent to the air inlet of the core of a jet engine, to suction off air and reduce fan wake blockage at the core inlet. The slots may be through the pressure surface adjacent the blade tip edge of fan blades to reduce blade tip leakage effects.

Centrifugal air flow control

An actuation system for pivoting a flap on a helicopter rotor blade to reduce the interaction of the blade with the preceding blade vortex. The actuation system includes a fluid supply which is connected to first and second fluid supply lines. The fluid supply lines convey flows of pressurized fluid from the fluid supply to an actuator. The actuator includes a housing mounted within the rotor blade and having a channel formed in it. A butterfly shaft is pivotally mounted within the channel and has laterally extending arms which separate the channel into four lobes. A first port connects the first fluid supply line with two diametrically opposed lobes in the channel. A second port connects the second fluid supply line with the other two diametrically opposed lobes in the channel. A torque coupling is attached to the butterfly shaft and engaged with the flap such that rotation of the torque coupling produces concomitant rotation of the flap. The pressurization of the first fluid supply line causes the torque coupling to rotate in a first direction. The pressurization of the second supply fluid line causes the torque coupling to rotate in the opposite direction.

High torque actuation system for an active rotor control system

A technique for providing a signal representative of blade vortex interaction (BVI) noise for a multi-blade rotorcraft. The fluid (air) pressure at one, two, or more predetermined locations on a rotor blade is measured during at least one predetermined azimuthal segment of blade rotation during operation to provide respective pressure measurements. The pressure measurements are processed to provide a signal for use as a control variable in a control system for the active control of BVI noise. The pressure measurements are made within 10% blade chord length of the blade leading edge and preferably two or more are made between 65% and 95% of blade radial-length. The pressure measurements are filtered and the band of retained frequencies is between 20 and 48 times the rotor rotation frequency. An algorithm operative over a determined blade frequency range optimizes the signal for control use.

Technique for providing a signal for controlling blade vortex interaction noise of a rotorcraft

In one embodiment for a helicopter main rotor assembly, a half-plow vortex generator is mounted in combination with the upper aerodynamic surface of each main rotor blade and is operative to generate a primary corotating vortex of sufficient strength to interact with and accelerate the dissipation of the tip vortex generated by the same main rotor blade, thereby reducing blade-vortex interaction noise radiating from the helicopter main rotor assembly. The half-plow vortex generator has a right triangular planform configuration defined by a length, a width, and an apex angle. The three-dimensional configuration of the vortex generator is further defined by an apex height. The apex height is the primary determinant of the strength of the generated primary corotating vortex and is defined in terms of the thickness of the main rotor blade at the local chord where the vortex generator is mounted. The apex height may be approximately equal to the local thickness, but preferably has a magnitude within the range of about one-eighth to about three-quarters of the local thickness. The length, width, and apex angle are secondary determinants of the strength of the primary corotating vortex generated by the half-plow vortex generator. The length and width of the vortex generator are defined in terms of the tip chord length of the main rotor blade, the length preferably having a magnitude within the range of about one-fourth to one-half of the tip chord length and the width preferably having a value of about one-third of the length of the vortex generator. The apex angle preferably has a value within the range of about twenty to about thirty degrees. The mounting site for the half-plow vortex generator is defined in terms of the length of the local and tip chords, respectively. The vortex generator is mounted inboardly from the tip of the main rotor or blade a spanwise distance having a magnitude preferably within the range of about one-half of to about equal to the tip chord length in substantial alignment with the local chord. The apex of the vortex generator is mounted inwardly from the leading edge of the main rotor blade by a chordal distance having a magnitude of about one-quarter the local chord length.

Growing community of inventors

Southbury, CT, United States of America

Peter F Lorber