Abstract: An aircraft includes an airframe, an extending tail, a counter rotating, coaxial main rotor assembly including an upper rotor assembly and a lower rotor assembly, and a translational thrust system positioned at the extending tail. The translational thrust system provides translational thrust to the airframe. An upper hub fairing is positioned at the upper rotor assembly. A lower hub fairing is positioned at the lower rotor assembly. A shaft fairing is disposed between the upper hub fairing and the lower hub fairing. The upper hub fairing is substantially sealed to the shaft fairing and the lower hub fairing is substantially sealed to the shaft fairing.

Abstract: There is described a method and system for in-flight start of an engine. The method comprises rotating a propeller; generating electrical power at an electric generator embedded inside a propeller hub from rotation of the propeller; transmitting the electrical power from the electric generator to an engine starter mounted on a core of the engine via an electric power link; and driving the engine with the engine starter to a sufficient speed while providing fuel to a combustor to light the engine to achieve self-sustaining operation of the engine.

Abstract: A turbine engine module including an upstream propulsive unit including a propellers doublet that are upstream and downstream, respectively mounted around an axis, a power turbine shaft with axis of rotation intended for rotating the propellers doublet, a speed reducer connected to the propellers doublet and driven by the shaft, and, a pitch-changing system including a cylinder that controls the pitch of the blades of the upstream propeller the rotational axis of the propellers doublet is shifted in relation to that of the shaft. The cylinder is placed downstream of the reducer, and the pitch-changing system includes a shaft for controlling the pitch of the blades that connect the cylinder to the blades of the upstream propeller.

Abstract: A distributed propulsion system is described that includes at least one turbine engine including an engine shaft and at least one mechanically driven propulsor, wherein a propulsor shaft of the at least one mechanically driven propulsor is not co-axial with the engine shaft of the at least one turbine engine and is driven by the engine shaft of the at least one turbine engine. The distributed propulsion system further includes at least one generator driven by rotation of at least one of the engine shaft of the at least one turbine engine or the propulsor shaft of the at least one mechanically driven propulsor. The distributed propulsion system also includes at least one electrically driven propulsor, wherein a propulsor motor of the at least one electrically driven propulsor drives a propulsor fan of the at least one electrically driven propulsor based on electricity produced by the at least one generator.

Abstract: Pitch actuation system for a turbine engine propeller, comprising an actuator, a movable part of which is configured to be connected to blades of the propeller so as to rotate them relative to the blade pitch axes (B), comprising: a transmission screw that can rotationally and translationally move along a longitudinal axis (A), a nut, through which said transmission screw passes and which cooperates with this screw so as to translationally displace along the axis (A) with a view to modifying the pitch of the propeller blades, and means for decoupling between the rotation of the propeller and said nut, which is rotationally fixed; first blade pitch control means, which comprise at least one electric motor setting a component into rotation through a planet reduction gear with a view to modifying the position of the transmission screw; second blade feathering means configured to act on the transmission screw with a view to modifying the pitch of the blades if the first means are inactive, and in that said fir

Abstract: A distributed propulsion system includes a first propulsor and a second propulsor, a first generator configured to generate a first AC current, and a second generator configured to generate a second AC current. The system includes a power regulation circuit. The power regulation circuit includes a first current path that includes a first power electronics circuit, a second current path that includes a second power electronics circuit, a third current path that bypasses the first and second power electronics circuits, and a fourth current path that bypasses the first and second power electronics circuits. The power regulation circuit also includes a plurality of switches configured to selectively couple each respective input to a respective selected output to cause a respective current to flow from the respective input to the respective selected output via one of the first current path, second current path, third current path, or fourth current path.

Abstract: A system is configured to change the pitch of blades of at least one turbine engine propeller provided with multiple blades. The system includes a control means acting on a connecting mechanism connected to the blades of the propeller. The control means includes a stationary body and a movable body translatable along a longitudinal axis (X) relative to the stationary body and defining two chambers. A fluid supply means is configured to be connected to a fluid supply source and to supply the chambers. The fluid supply means includes at least one channel. The channel is arranged and extends along an axis (Q) parallel to the longitudinal axis in an overthickness of a wall of the stationary body, the overthickness extending radially inside relative to the longitudinal axis.

Abstract: A method and system for controlling a pitch of blades of a fan assembly having a centerline axis of rotation is provided. The system includes a pitch change mechanism (PCM) including a hydraulic actuator positioned axisymmetric with respect to the fan assembly and configured to angularly displace the blades of the fan assembly between a first position and a second position. The PCM further includes a plurality of hydraulic fluid supply lines coupled in flow communication between the hydraulic actuator and a hydraulic fluid transfer sleeve, the hydraulic fluid transfer sleeve configured to transfer a flow of pressurized hydraulic fluid across a gap between a stationary member of the hydraulic fluid transfer sleeve and a rotatable member of the hydraulic fluid transfer sleeve.

Abstract: Pitch control assembly and propeller blade assembly having a spider hub are disclosed. The spider hub includes a hub and a set of arms spaced circumferentially about the hub and projecting radially from the hub, wherein the set of arms are configured to receive a set of blades such that a blade root of a blade is rotationally mountable into an arm included in the set of arms, a crosshead located within the hub and axially moveable relative to the hub, a torque tube located in the arm and extending into the hub, wherein a pitch angle of the blade can be adjusted by axially moving the crosshead to rotate the torque tube to effect a corresponding rotation of the blade.

Abstract: An example electrical power system includes a DC bus connected to a load, a plurality of generators driven by rotation of a common shaft, and a plurality of power converters. Each power converter includes an active rectifier controller that operates a respective active rectifier to rectify AC from a respective one of the generators to DC on the DC bus. A load sharing controller is operable to provide a respective adjustment signal to each respective power converter that is enabled, the respective adjustment signals based on a difference between an average output current across all of the active rectifiers that are enabled, and a particular output current of the respective power converter. Each active rectifier controller is operable to determine a quadrature current value for its associated generator based on its adjustment signal.

Abstract: A turbofan engine includes a turbine engine having a rotatable fan and a generator. The generator further includes a main machine, an exciter, and a generator control unit for controlling the excitation of the main machine. A rotor assembly is located within one of the blades, and a stator assembly that is along a rotational path of the rotor assembly whereby the operation of the turbine engine rotates the fan, which rotates the rotor assembly along its rotational path past the stator assembly to generate electricity.

Abstract: Systems and methods for de-icing a fan of a gas turbine engine are disclosed. The systems and methods may include an electrical coil operatively associated with a first rotating surface of the fan; a magnet operatively associated with a second rotating surface of the fan, the second rotating surface rotating in a direction counter to the first rotating surface, the magnet and the electrical coil thereby producing electricity when the fan is in motion; and a heating element operatively associated with a surface on the fan, the heating element being powered by the electricity produced by the magnet and the electrical coil.

Abstract: A gas turbine engine includes a fan including a plurality of fan blades rotatable about an axis, a compressor section, a combustor in fluid communication with the compressor section, a turbine section in fluid communication with the combustor, a geared architecture arranged in a housing and driven by the turbine section for rotating the fan about the axis, and a support member that supports the geared architecture within the gas turbine engine. The support member includes an inner portion and an outer portion. One of the inner and outer portions is configured to be coupled to the geared architecture and the other of the inner and outer portions is configured to be coupled to the housing. A plurality of removal features each have at least one engaging surface to facilitate a pulling force on the support member in a direction parallel to the axis.

Abstract: Systems and methods for de-icing a fan of a gas turbine engine are disclosed. The systems and methods may include an electrical coil operatively associated with a first rotating surface of the fan; a magnet operatively associated with a second rotating surface of the fan, the second rotating surface rotating in a direction counter to the first rotating surface, the magnet and the electrical coil thereby producing electricity when the fan is in motion; and a heating element operatively associated with a surface on the fan, the heating element being powered by the electricity produced by the magnet and the electrical coil.

Abstract: The present invention provides a drag-type turbine capable of efficiently extracting kinetic energy of fluid particles orbiting in waves and a wave power generator comprising said drag-type turbine. This turbine is a single bucket drag-type turbine with a single half-pipe bucket and a counterweight oppositely facing the bucket, where fluid particles in orbital motion in a wave impel the bucket and the counterweight to rotate them as a unitary body.

Abstract: An electrical power supply including an asynchronous machine, an arrangement for driving a rotor of the asynchronous machine in rotation by a rotor of an engine, and an electrical connection for powering electrical equipment by the rotor of the asynchronous machine. The asynchronous machine is configured to receive AC electrical power via a stator of the asynchronous machine, and it presents, over a predetermined range of drive speeds of the rotor of the asynchronous machine under drive by the rotor of the engine, efficiency in transferring electrical power from the stator to the rotor that is privileged relative to the efficiency with which rotary mechanical power is converted into electrical power.

Abstract: A contra-rotating propeller system for an aircraft turbine engine, including a free power turbine including a first rotor and a second rotor contra-rotating relative to the first rotor, a first contra-rotating propeller and a second contra-rotating propeller to be rotated about a longitudinal axis of the propeller system relative to a stator of the system, and a mechanical transmission device. The mechanical transmission system is provided between the first propeller and the second propeller.

Abstract: A propulsion engine for an aircraft includes a first fan having a set of first blades and a second fan having a set of second blades. There is provided a first angular pitch adjustment mechanism coupled to the first set of blades, a second angular pitch adjustment mechanism coupled to the second set of blades and an actuation device coupled to the first angular pitch adjustment mechanism. The first and second angular pitch adjustment mechanisms are coupled together such that when the actuation device generates an output, the angular pitch of each of the first blades and each of the second blades changes.

Abstract: A turboprop provided with a blade-positioning device including a stationary nacelle, a rotary nacelle including a plurality of blade roots, a turbine, the stationary and rotary nacelles and the turbine being coaxial along a longitudinal axis, a blade positioning device including for each blade a device configured to transform movement suitable for transforming a translation movement into a rotation movement, each one of the device for transforming movement being secured to the rotary nacelle and being suitable for pivoting a blade. The positioning device is placed between the inner surface of the stationary nacelle and the outer surface of the turbine, the positioning device including a member including a body secured to the stationary nacelle and a rod for sliding along an axis substantially parallel to the longitudinal axis.

Abstract: The invention provides an emergency power network for aircraft, for powering actuator motors (4) connected to the network, the network comprising a power bus (11) adapted to convey three-phase AC power generated by at least one DC/AC converter (12) that is powered by a DC source of the aircraft, the converter being fitted with modulator means for modulating the voltage and/or the frequency of the three-phase power generated thereby.

Abstract: A pitch drive device capable of emergency operation by adjusting the rotor blade pitch of a wind or water power plant. The pitch drive device includes an inverter device and a three-phase current drive motor preferably a three-phase IPM synchronous motor. A direct current power storage device can be substantially directly connected to an intermediate direct current circuit, at least for emergency operation, between a rectifier device and the inverter device for at least briefly supplying power to the synchronous motor, so that the IPM synchronous motor can be operated under speed control when the intermediate circuit voltage UZK is falling. The device enables speed-controlled emergency operation of the pitch drive device at high torque when an intermediate circuit voltage UZK is falling in emergency operation, wherein the direct current energy storage device can, improve the efficiency as an energy buffer, and reduce current transfer via the rotor slip ring.

Abstract: A system of contra-rotating propellers for an aircraft jet engine, including: a free power turbine; a first and second propeller, contra-rotating, the first propeller being placed in a predetermined direction relative to the second propeller, each including a hub, an outer ferrule, and coupling arms linking the two; and a casing inserted between the free turbine and the propellers, the propellers arranged in the predetermined direction relative to the casing and the free turbine arranged in the opposite direction relative to the casing, the casing including a casing extension in the given direction, rotatably supporting the hub of the propeller. The coupling arms extend in the opposite direction, radially towards the outside.

Abstract: A method of controlling a Counter-Rotating Open-Rotor (CROR) includes measuring a speed of a first rotor and deriving a speed of a second rotor and controlling a pitch of the first rotor and the second rotor.

Abstract: A rotary wing vehicle includes a body structure having an elongated tubular backbone or core, and a counter-rotating coaxial rotor system having rotors with each rotor having a separate motor to drive the rotors about a common rotor axis of rotation. The rotor system is used to move the rotary wing vehicle in directional flight.

Abstract: A system of counter-rotating propellers for an aircraft turbine engine including a first and a second propeller, each including a stalling control system for the blades, a rotating actuating mechanism for sliding an element to move the angle of attack of the blades, and a disengaging mechanism for rigidly fixing in rotation the rotating actuating mechanism. The system is designed so that when the disengaging mechanism is engaged, a relative rotation speed is created between the elements and the associated rotating actuating mechanism thereof, bringing the blades into a neutral position thereof for feathering.

Abstract: A propeller arrangement has a first propeller assembly providing a row of first propellers, and a second propeller assembly, rearward of the first propeller assembly, providing a row of second propellers. The first and second propellers are radially extendable and retractable. The propeller arrangement further has a control system for controlling the extension and retraction of the first and second propellers. The control system is arranged such that when the propellers of one of the first and second propeller assemblies extend, the propellers of the other of the first and second assemblies retract.

Abstract: A variable-pitch propeller or fan comprises a hollow boss, a number of propeller blades fitted rotatably on the boss, and also an adjusting element which is axially slidable in the boss and has a number of grooves running essentially at right angles to the direction of sliding, each propeller or fan blade having a control pin which is placed eccentrically relative to its rotary shaft and is slidingly accommodated in a groove of the adjusting element. In order to increase the range of adjustment each groove comprises an essentially straight part and also a second part connecting to the straight part and forming an angle with the essentially straight part.

Abstract: A propeller for an aircraft or fan comprises an even number of propeller blades, at least six in number, which are unsymmetrically arranged around the axis of roation of the propeller in two circumferentially equidistantly spaced groups of at least three blades each. Each blade of each group is paired and longitudinally aligned with a respective blade of another group at the opposite side of the axis of rotation of the propeller, and each two next adjacent blades in each group are offset relative to each other by a spacing angle of between about 15.degree. and 40.degree.. For a selected speed of rotation of the propeller corresponding to a particular blade-tip Mach number, the magnitude of the spacing angle is inversely related to the magnitude of that blade-tip Mach number, for effecting a reduction of the level of the rotational sound harmonics by interference.

Abstract: A variable pitch propeller module includes first and second multi-bladed propellers arranged to be driven in opposite rotational directions by a reduction gear mechanism, via shafts. First and second drums are rotatably mounted on the hubs of the first and second propellers and the drums are arranged to rotate the blades of the propellers. A hydraulic motor is mounted coaxially on and rotates with the second propeller, the hydraulic motor being arranged to drive the drums by via a pitch change gear assembly. A hydraulic fluid feed tube extends coaxially through the reduction gear mechanism and both propellers to supply hydraulic fluid to the hydraulic motor. An annular sleeve is positioned coaxially on the tube. The hydraulic fluid feed tube has passages and the sleeve has passages which are aligned to allow hydraulic fluid to flow to the hydraulic motor to vary the pitch of both blades. The feed tube and sleeve are moved axially to control the flow of hydraulic fluid to the hydraulic motor.

Abstract: A propeller for an aircraft or a blower or fan, wherein the propeller blades are intended for operation at speeds characterized by blade tip Mach numbers in the range of about 0.4 to 0.8, comprises at least two pairs of diametrically opposed blades, the blade pairs being arranged at a spacing angle .epsilon. of between about 15.degree. and 50.degree. between them, and the magnitude of the spacing angle being inversely related to the magnitude of the blade tip Mach numbers, thereby to effect a reduction in the level of the rotational sound harmonics by interference. The pairs of blades may be axially spaced from one another, i.e., arranged in respective spaced parallel planes of rotation, shifted, with the rear one of two adjacent blades leading in the direction of rotation.

Abstract: An electric motor driven blade pitch varying system for the fan blades of an unducted fan type aircraft gas turbine engine utilizes permanent magnet alternating current motors located in the oil sump region of the engine. An alternator driven by the engine generates unregulated variable frequency, variable amplitude power which is rectified and placed on a DC bus. Controlled inverters convert the DC power on the bus to appropriate AC power for the motors. The system incorporates redundancy without significant weight penalty by providing alternators and motors dividing into two independent operating sections on common shafts. Separate electronic circuits are provided to supply power for each sectionalized motor or to rectify power from each alternator section. A common power bus may be used to couple the multiple motors and alternators. The common bus may alternatively receive power from tbe aircraft 400 Hz system or from on-board batteries.

Abstract: A lightweight counterrotatable propeller system driven by a rotatable shaft is disclosed. The system includes first and second counterrotatable propellers, each propeller including a plurality of blades mounted on first and second hubs, respectively. Each blade is attached to the hub by means of a ball screw which converts centrifugal force on each of the rotating propeller blades into a pitch changing force. Gearing means for operatively connecting the shaft with each propeller are located between the propellers with a carrying member for one of the propellers forming an outer wall which radially bounds the gearing means. Additionally, non-rotating actuating means for changing propeller pitch are operatively connected to the blades of each of said first and second propellers through first and second thrust bearings, respectively.

Abstract: A counterrotatable bladed rotor assembly drivable by a rotatable shaft comprises a leading propeller, a trailing propeller, and a gearbox located axially between the two propellers and enclosed by a non-rotatable casing having an end for attachment to a support structure. The gearbox has a first output shaft to the leading propeller and a second output shaft to the trailing propeller. A first fluid-pressure operable actuator is provided to vary the pitch of the blades of the leading propeller, and a second fluid-pressure operable actuator is provided to vary the pitch of the blades of the trailing propeller. In addition passageways are provided to connect the first and second actuators to a source of fluid under pressure. The casing rotatably supports the second output shaft at a position between the gearbox and the leading propeller and rotatably supports the first output shaft at a position between the gearbox and the trailing propeller.

Abstract: A propeller module for an aero gas turbine engine comprising two contra-rotating propellers has a reduction gear train positioned axially between the propellers. Pitch change mechanism are provided to change the pitch of the blades of both propellers independently of the differential speed of the propellers. The pitch change mechanisms comprise two sets of hydraulic motors one set of which is mounted on a carrier member of the gear train within the planet gears, the other set is mounted on the hub of the second propeller. Pitch selector valves control the supply of hydraulic fluid to the hydraulic motors, and the pitch selector valves are operated by a pitch change power unit. The pitch selector valves are positioned coaxially of the propellers and a transfer tube extends coaxially between the pitch selector valves to transfer hydraulic fluid therebetween independently of differential speed of the propellers.

Abstract: The basic characteristics of an airplane and of a helicopter are combined into one flying craft: a HELIPLANE. This aircraft can fly forward like an airplane and hover like a helicopter. In the hovering mode, the craft lifting force is generated by gyrating blades and the craft control forces and moments are provided by a tail end propeller. In the forward flying mode, the craft lifting forces are generated by two wings and the gyrating blades. The propeller alone provides the forward propulsive thrust. The operations of the gyrating blades, of the craft control surfaces and of the power plant are all integrated, monitored and controlled to coordinate such operations during hovering, forward flight and any transition phase between hovering and forward flight. The gyrating blades never generate any forward propulsive thrust. The cyclic pitch motion of the gyrating blades needed to accommodate the craft forward flight velocity is induced by this forward velocity.

Abstract: A propeller module for a gas turbine engine comprising two contra-rotating propellers has a reduction gear positioned axially between the propellers. Pitch change mechanisms are provided to change the pitch of the blades of both propellers independent of the differential speed of the propellers.

Abstract: A propeller module for an aero gas turbine engine comprises two contra-rotating propellers driven by a reduction gearbox positioned axially between the propellers.Pitch change mechanisms operated by a pitch change power unit are provided to change the pitch of the propeller blades. The pitch change power unit is positioned in the hub of the second multi-bladed propeller and is remote from the first multi-bladed propeller. The first and second pitch change mechanisms are mounted on the reduction gearbox. The first pitch change mechanism comprises first pitch change gears which are rotatably mounted on a carrier of the reduction gearbox by spindles which extend axially through planet gears of the gearbox. The second pitch change mechanism comprises second pitch change gears rotatably mounted on the carrier.

Abstract: Blade pitch varying means for use in a gas turbine engine are disclosed. The blade pitch varying means may be used on an engine with a single row or two counterrotating rows of variable pitch blades which are disposed outwardly from an annular gas flowpath and which are connected with a rotating airfoil within the flowpath. The blade pitch varying means comprise actuation means, bearing means, and gearing means. The actuation means are in a nonrotating reference frame disposed inwardly from the flowpath and deliver an axial force. The bearing means transmit the axial force from the nonrotating into a rotating reference frame which contains both the propulsor blade and the airfoil in the gas flowpath. The gearing means are located in the rotating reference frame and convert the axial force into a force for varying the blade pitch.

Abstract: An improved counterrotating power turbine is disclosed. The power turbine includes a support having an annular axial cross-section and forward and aft portions. The forward portion of the support has a diameter greater than the diameter of the aft portion. Also included are a first rotor and a second rotor. The first rotor is supported on the first portion of the support by first bearing means and extends to the aft portion forming a first interface therewith. The second rotor is supported on the first rotor by second bearing means and extends to the aft portion of the support forming a second interface therewith. In this manner, it is possible to have low diameter slip rings at the first and second interfaces while maintaining relative high diameters for the rotor bearing means.

Abstract: Multiple flat-plate blade rows of pitch adjustable blades are offset mounted in a manner such that when flat-plate blades in adjacent rows are aligned at a specific pitch setting, respective flat-plate blades of the adjacent rows nearly mate. The offset between the flat-plate blade rows functions to produce unequal pitch angle settings of the blades of adjacent rows which, in turn, function to produce the result that the respective flat-plate blades which nearly mate, in combination, produce a blade configuration which has an effective camber.

Abstract: An aircraft propulsion means 20 comprises a multibladed, unshrouded, propeller fan 27 adapted in a cruise condition to operate at such high disc loadings that a substantial component of swirl is imparted to the slipstream in a given sense, and swirl reducing means (for example a multi-bladed stator 35) arranged with respect to the propeller fan to impart a considerable component of swirl in the opposite sense, whereby the total swirl imparted to the slipstream is nil or relatively low.

Abstract: The action of upstream and downstream foil sets rotating on a common shaft within a fluid is enhanced by fixing certain interrelations of the foils such as the axial distance between the foils, the radial index between foils and pitch of one foil relative to the other so that the foil stages are fixedly mounted with the foils of each stage being symmetrically and equidistantly spaced from one another and from the foils of the next adjacent foil stage so that the interacting uniform adjacent foil pressures and the upstream foil wake beneficially interacts optimally with at least one of the surfaces or boundary layers of the foils of the next adjacent downstream foil stage.

Abstract: An analog mixer for a helicopter rotor control system mounted for tilting motion about a variable tilt axis and connected to the rotor control swashplate to cause synchronous tilting and including means to impart tilt generating control inputs to the analog mixer, and means to vary the position of the analog mixer tilt axis as a function of helicopter speed to thereby vary the phase angle of the helicopter rotor without imparting control inputs to the rotor control swashplate.

Abstract: A gas turbine engine of a ducted-fan bypass type includes a fan with a plurality of circumferentially spaced airfoils thereon each including first and second portions thereof defining a forward thrust airfoil having a chord to blade spacing ratio greater than one. Each of the first and second portions are rotatably supported on the fan hub and are movable from a forward thrust position when the trailing edge of the first portion is juxtaposed against the leading edge of the second portion to a reverse thrust position wherein the first and second portions are corotated so as to locate the leading edge of the first portion in juxtaposed relationship to the trailing edge of a second portion to define a reverse thrust airfoil for producing a reverse flow of air through the fan duct passage with a resultant reverse thrust action on the gas turbine engine.