Abstract: A helicopter with a longitudinal axis and with a tail portion (1) with a transverse duct (6) and a drive shaft (23) inside a drive shaft fairing (14) for an aerodynamic and acoustic optimized counter-torque device (2) supported within said transverse duct (6).

Abstract: My invention is a helicopter having a front electric anti-torque rotor for the purpose of having a mechanically driven pusher propeller at the rear for increasing forward speed. Speed has been a limiting factor in vertical flight. Various designs have been conceived by people around the world to make helicopters go faster. My design is a high speed single rotor helicopter design that uses a gas-electric hybrid front electric anti-torque rotor system to allow for a mechanically driven pusher propeller at the rear. As the helicopter goes forward, the front electric anti-torque gives control and the mechanically driven pusher propeller at the rear gives increased forward speed. The intent of the design is to make a high speed single rotor helicopter design.

Abstract: A gyroplane comprises a fuselage 1 with a cockpit, with a folding strut mounted on it, a rotor head 3, with adjustable torsional hub 16 and pusher propeller 5 with adjustable pitch. In order to uniformly distribute the load applied on the torsional hub 16, on the rotor head 3 while prespinning of the rotor blades 4, the torsional bar is performed from substantially straight composite plates. In order to reduce vibration on the control stick in-flight, the surface of fastening the rocking joint 15 of the torsional hub 16, is turned at the angle not more than 40 degrees to the longitudinal axis of the torsional hub 16 of the rotor blades 4. In order to reduce the load applied on the gyroplane control stick in-flight, the rotor head 3 is fastened to the strut through a frame joint 9 with trunnion offset forwardly in pitch. In order to set the thrust rating in-flight, the pusher propeller 5 is provided with an adjustable torsional hub 16 performed of composite plates.

Abstract: A tailwheel assembly for an aircraft includes a ventral fin including a fixed airframe portion of the ventral fin and a moveable tailwheel portion of the ventral fin. A tailwheel strut extends through the ventral fin and includes a fixed first strut portion and an extendable second strut portion having the moveable tailwheel portion of the ventral fin secured thereto. A tailwheel is secured to the extendable second strut portion. A method of operating a tailwheel assembly for an aircraft includes extending an extendable portion of a tailwheel strut from an airframe of the aircraft. The tailwheel strut has a tailwheel secured thereto and is located at least partially in a ventral fin of the aircraft. A tailwheel portion of the ventral fin is moved away from a fixed airframe portion of the ventral fin via extension of the extendable portion of the tailwheel strut.

Abstract: A rotary wing aircraft propulsion system includes an engine, a heat exchanger cooling a fluid from the engine and a thermoelectric generator in thermal communication with the fluid to generate electrical power. The thermoelectric generator provides electrical power to at least one aircraft component.

Abstract: A rotor system for a rotorcraft, the rotor system is a rotor hub having six rotor blades attached to a rotor mast via a rotor yoke assembly. Each rotor blade is angularly spaced in 30° and 90° alternating angular increment about a mast axis of rotation. Such rotor blades spacing reduces the vibration that is translated into the rotorcraft through the rotor mast.

Abstract: A helicopter (1) has a horizontal rotor (2) driven for rotation about a vertical rotor axis (4), and a tail (9) extending backwards from the rotor axis (4) at a fixed angle (10) between about 20° and about 60° to a vertical longitudinal middle plane (7) of the helicopter (1) on a retreating blade side of the horizontal rotor (2). The tail (9) comprises a profiled body (16) including aerodynamic effective surfaces (19, 20) for selectively generating lift on the retreating blade side of the horizontal rotor (2) in forward flight of the helicopter (1). For hovering flight of the helicopter (1), the profiled body (16) can be swiveled about a swivel axis running parallelly to the main axis (21) of the tail for reducing a cross-sectional area of the profiled body facing the horizontal rotor (2).

Abstract: An aircraft including a fuselage with a yaw axis, a pitch axis and a roll axis, two attitude control thrusters, fixedly connected to the fuselage to provide thrust parallel to the yaw axis, two locomotion and hover thrusters. The aircraft further includes for the locomotion and hover thruster, a mechanism for tilting the locomotion and hover thruster about a tilt axis parallel to the pitch axis to select a direction, parallel to a first plane defined by the yaw and roll axes, in which the locomotion and hover thruster provides thrust.

Abstract: A tail assembly (10) for a rotorcraft (20), the tail assembly (10) comprising a first stabilizer (3) extending transversely on either side of an anteroposterior plane (P1), and a second stabilizer (4, 4?) extending in elevation. Two propellers (31, 41) positioned on either side of the anteroposterior plane (P1) provide the rotorcraft (20) with at least part of its yaw control and its propulsion. The axes of the two propellers (31, 41) are situated in a plane substantially parallel to the horizontal plane (P3) and they intersect at a position in the anteroposterior plane (P1) of the rotorcraft (20) that is located between the front end of the rotorcraft (20) and the propellers (31, 41). Using both propellers (31, 41) of the tail assembly (10) simultaneously makes it possible to provide the rotorcraft (20) with longitudinal thrust while conserving its transverse thrust for the anti-torque function, it being possible to control these two thrusts independently.

Abstract: The utility model provides an airplane model control system capable of conducting omnidirectional and long-distance transmission of signals without being interfered by the sunlight and other visible lights. The airplane model control system can transverse obstacles for data communication, and comprises a remote control transmitting control device and an airplane receiving control device which all work in the frequency band of 2.4 GHz and 83 communication channels are included; and each remote control transmitting control device has unique ID number, which will not be controlled and interfered due to the reason of same frequency, realizes a share port of multiple functions simultaneously on one main controller and can realize reduction of cost.

Abstract: The invention relates to compensation for the torque which is produced by the main rotor (110) of a helicopter (100). The apparatus according to the invention for torque compensation is intended for a helicopter whose main rotor rotates about a rotation axis (RH) during operation and thus produces a torque, which acts on the fuselage (120) of the helicopter and would cause it to rotate. The apparatus comprises a lateral flow fan (200) having a housing (210) and having a rotor (220) which is mounted in the housing, wherein the lateral flow fan is arranged on the tail boom (130) of the helicopter such that it produces a thrust effect (F) during operation which compensates for the torque of the main rotor.

Abstract: The rotors of a helicopter are directly connected with electric high-torque motors, and are powered by the latter. Energy generation and rotor drive are separate from each other. The high-torque motor of the main rotor is pivoted to the cabin canopy, so that it can be tilted together with the main rotor.

Abstract: A torque resisting device for a helicopter, wherein the helicopter includes a body and a main rotor. The device includes a deflector secured to and movable relative to the body, wherein the body includes opposing lateral sides and the deflector is movable to a position to extend away from only one of the lateral sides of the opposing lateral sides. The deflector includes a dimension extending in a plane generally non-parallel to a plane of the main rotor. Further included is a method for counteracting a torque created by the rotation of a main rotor of a helicopter.

Abstract: A tail boom adapted for counteracting a fuselage torque created by an engine carried by a fuselage of a rotary aircraft. The tail boom is positioned within the rotorwash from the rotary and includes a first side surface contoured to create a low-pressure region of an airfoil and a second opposing side surface contoured to create a high-pressure region of an airfoil. The pressure difference between the high-pressure region and the low-pressure region causes the tail boom to move towards the low-pressure region, resulting in a lateral force opposing the torque on the fuselage.

Abstract: A ducted fan for a helicopter includes a transverse duct and a counter-torque device supported within the duct. The counter-torque device includes a rotor rotatably mounted within the duct and a stator fixedly mounted within the duct downstream from the rotor. The rotor includes a rotor hub having a rotor axis, and rotor blades extending from the hub. The Rotor blades have a modulated angular distribution about the rotor axis. The stator includes a stator hub, and a plurality of stator vanes distributed around the stator hub. The stator vanes are angularly modulated around the stator hub.

Abstract: My invention is a helicopter having a front electric anti-torque rotor for the purpose of having a mechanically driven pusher propeller at the rear for increase forward speed. Speed has been a limiting factor in vertical flight. Various designs have been conceived by people around the world to make the helicopter go faster. My design is a high speed single rotor helicopter design that uses a gas-electric hybrid front electric anti-torque rotor system to allow for a mechanically driven pusher propeller at the rear. As the helicopter go forward, the front electric anti-torque gives control and the mechanically driven pusher propeller at the rear gives increase forward speed. The intent of the design is to make a high speed single rotor helicopter design.

Abstract: An unmanned aerial vehicle helicopter including a dismountable tail section including a torque compensating rotor. Power transmission from the motor to the torque compensating rotor is accomplished by pulley-and-belt drive arrangements.

Abstract: A vibration suppression system for a rotorcraft having an airframe, a main gear box, a rotor, a hub, and a rotor head, said system comprising a hub mounted vibration suppressor (HMVS) mounted on the rotor head to reduce in-plane loads that the rotor exerts on the hub; and a plurality of active vibration control (AVC) actuators grouped in an overhead of the airframe beneath and proximate to the main gear box, to reduce residual loads.

Abstract: The invention is related to a helicopter (10) comprising a main rotor (12), a cycloidal rotor (14) and a rotating cylinder (18). The rotating cylinder (18) extends along a longitudinal axis of a tail boom (13). The cycloidal rotor (14) extends at least partly along said same tail boom (13) and rotates outside the rotating cylinder (18).

Abstract: A gyroplane comprises a fuselage 1 with a cockpit, with a folding strut mounted on it, a rotor head 3, with adjustable torsional hub 16 and pusher propeller 5 with adjustable pitch. In order to uniformly distribute the load applied on the torsional hub 16, on the rotor head 3 while prespinning of the rotor blades 4, the torsional bar is performed from substantially straight composite plates. In order to reduce vibration on the control stick in-flight, the surface of fastening the rocking joint 15 of the torsional hub 16, is turned at the angle not more than 40 degrees to the longitudinal axis of the torsional hub 16 of the rotor blades 4. In order to reduce the load applied on the gyroplane control stick in-flight, the rotor head 3 is fastened to the strut through a frame joint 9 with trunnion offset forwardly in pitch. In order to set the thrust rating in-flight, the pusher propeller 5 is provided with an adjustable torsional hub 16 performed of composite plates.

Abstract: A torque resisting device for a helicopter which comprises a body, a first rotor and a tail rotor wherein the device comprises a deflector secured to and moveable relative to the body, wherein the deflector is positioned between the main rotor and the tail rotor and wherein the deflector is positioned generally aligned with the body in a non-deployed position and a portion of the deflector is positioned spaced apart from the body in a deployed position. Additionally, a method to counteract torque in the operating of a helicopter.

Abstract: Improvements in a helicopter with a remote control is presented the helicopter has a stacked main rotor to provide vertical lift and control. A plurality of outrigger rotors provides side-to-side stability as well as allowing the body of the helicopter to tip side-to- side. The helicopter further includes an angled tail rotor to provide angular tip to the helicopter as well as providing forward thrust. The remote control is configured as a single stick design. The single stick design allows a user to control the lift of the helicopter with a trigger control for the speed of the main rotor and thumb controlled joystick provides directional movement. The joystick can also provide a charging station for the helicopter where the batteries and the charging cable can be concealed completely within the controller.

Abstract: A helicopter auxilary anti-torque system for efficiently supplying thrust and control at the tail of a helicopter during failure of the helicopter tail rotor. The helicopter auxilary anti-torque system generally includes a fluid thrust assembly selectively engageable onboard the helicopter, an auxiliary tail rotor selectively engageable onboard the helicopter, and at least one controller to operate the fluid thrust assembly and the auxiliary tail rotor to effect a controlled anti-torque force of the tail boom during failure of the conventional helicopter tail rotor. The fluid thrust assembly projects a non flammable fluid from the tail boom of the helicopter. The auxiliary tail rotor is collapsible within the tail boom of the helicopter when not in use. The fluid thrust assembly and the auxiliary tail rotor may be automatically activated in the case of the primary tail rotor failure, or activated by the pilot of the helicopter via one or more switches.

Abstract: The rotary wing aircraft is based on the principle of the gyroplane, and includes a double wing rotating in opposite directions, coupled to a power converter which transfers the power of the gyroplane engine for launching by a mechanical converter which provides the lift energy and which, under command from the airframe, transposes the power to the horizontal thrust propeller. The aircraft is put into natural lift mode by its translational speed, this operating principle allowing take-off at low wind speeds which do not allow auto-rotation to be established.

Abstract: A fairing (1) for a structural element of a rotorcraft, the fairing including a rear portion (2) that is substantially orthogonal to the longitudinal direction (L) of the aircraft, extending between two spaced-apart trailing edges (3, 4) and thus presenting a determined width, said rear portion (2) closing at least part of the internal volume defined by the fairing (1) and generating aerodynamic drag in forward flight. According to the invention, the rear portion presents, at least at the trailing edges (3, 4), a shape that is perturbed on the streamlines (5) of the air-flow.

Abstract: Apparatus and methods for controlling yaw of a rotorcraft in the event of one or both of low airspeed and engine failure are disclosed. A yaw propulsion provides a yaw moment at low speeds. The yaw propulsion device may be an air jet or a fan. A pneumatic fan may be driven by compressed air released into a channel surrounding an outer portion of the fan. The fan may be driven by hydraulic power. Power for the yaw propulsion device and other system may be provided by a hydraulic pump and/or generator engaging the rotor. Low speed yaw control may be provided by auxiliary rudders positioned within the stream tube of a prop. The auxiliary rudders may one or both of fold down and disengage from rudder controls when not in use.

Abstract: A dual, coaxial rotor helicopter is provided that is relatively easy to fly. Thrust is provided by two ducted fans that are mounted at the rear of the aircraft and spaced apart laterally. Differential thrust generated by the fans provides yaw control for the aircraft, and forward thrust is provided by the fans working in combination. The coaxial rotors are preferably utilized primarily for lift, and not for forward thrust, which simplifies the control requirements. The coaxial rotor with ducted fan configuration also results in lower vibratory loads being imposed on the helicopter, thereby increasing its speed capability. The fan ducts serve to protect the fans, augment the fan thrust at low airspeeds, increase the efficiency of the fans at cruise speeds, and provide horizontal and vertical stabilizing surfaces to ensure aircraft flight stability.

Abstract: A method of piloting an aircraft (1) provided with at least one rotary wing (2) and a tail rotor (10) suitable for swiveling to pass reversibly from an anti-torque mode of operation to a propulsion mode of operation, said tail rotor (10) having a plurality of second blades (12) having a second variable pitch and rotating about an axis of rotation (AX), said axis of rotation presenting a first variable salient angle (?) relative to a first plane (P1). Thus, in the anti-torque mode of operation, said second pitch is controlled using first control means (31). Furthermore, in the propulsion mode of operation, said first salient angle (?) is controlled using first control means (31) and said second pitch is controlled using second control means (32) for controlling thrust.

Abstract: A blade for an antitorque tail rotor of a helicopter, having a leading edge and a trailing edge opposite each other and elongated along a longitudinal axis of the blade; the trailing edge, in use, interacts with the air current after the leading edge; the blade also has two opposite surfaces extending between the leading edge and the trailing edge, and a root portion extending from a radially inner first end, with respect to a rotation axis of the blade, towards a second end opposite the first end; and the root portion, when sectioned in a plane perpendicular to the leading edge and trailing edge, has a profile asymmetrical with respect to a chord joining the leading edge and trailing edge.

Abstract: A vertical take-off aircraft having a main power plant at the top of the aircraft to provide lift and an additional power plant to force air to travel in a horizontal direction to counteract the rotational force exerted on the main body of the aircraft by the main power plant. The additional power plant is connected to the aircraft such that tilting of the main power plant relative to the main body of the aircraft is able to cause the additional power plant to move relative to the main body of the aircraft.

Abstract: A toy helicopter includes a body, a rotor arrangement for generating a rotational power, and a foldable propeller blade including a bracket member coaxially mounted to the rotor arrangement and at least two blade leafs pivotally and symmetrically coupling with the bracket member in a horizontally movable manner to generate an evenly rotational motion thereof, so as to stably provide an upward force to lift up said body. When one of the blade leafs is pivotally folded by an external force to misalign the blade leafs with each other, the bracket member is kept rotating to generate a centrifugal force to essentially re-situate the blade leafs in line with each other so as to re-gain a control and balance of the body.

Abstract: This device, a modular minihelicopter, is a radio-controlled, gas-powered aircraft designed to perform varying missions based upon the functions of interchangeable modular-systems mounted on the minihelicopter's chassis.

Abstract: A helicopter includes a main rotor guided and protected in minor impacts by a guide-ring. In selected embodiments, the rotor is powered by an electric motor employing a magnetic field generator carried by the main rotor and stator coils installed on the guide-ring. The helicopter's main rotor thus effectively functions as the rotor of the electric power plant of the helicopter. In selected embodiments, the rotor's blades are arranged so as to create an opening in the center of the rotor, allowing pilot ejection or deployment of a parachute capable of safely lowering the helicopter in case of an emergency.

Abstract: A tail boom capable of creating propulsive force during forward flight to increase the forward speed is provided. A tail boom producing a force that cancels out a torque effect due to the Coanda effect by forcing airflow generated by a propeller disposed on an upstream side downward through a slit penetrating in the thickness direction and provided at a lower part of one side surface is configured such that the airflow generated by the propeller contributes to the propulsive force during forward flight.

Abstract: A helicopter auxilary anti-torque system for efficiently supplying thrust and control at the tail of a helicopter during failure of the helicopter tail rotor. The helicopter auxilary anti-torque system generally includes a fluid thrust assembly selectively engageable onboard the helicopter, an auxiliary tail rotor selectively engageable onboard the helicopter, and at least one controller to operate the fluid thrust assembly and the auxiliary tail rotor to effect a controlled anti-torque force of the tail boom during failure of the conventional helicopter tail rotor. The fluid thrust assembly projects a non flammable fluid from the tail boom of the helicopter. The auxiliary tail rotor is collapsible within the tail boom of the helicopter when not in use. The fluid thrust assembly and the auxiliary tail rotor may be automatically activated in the case of the primary tail rotor failure, or activated by the pilot of the helicopter via one or more switches.

Abstract: A tail rotor hub system and methods are disclosed. In one embodiment, the system includes a helicopter fuselage connected to a tail rotor assembly that holds tail blades. The assembly includes an elongated tail rotor housing and an elongated blade root fitting that rotates within the housing. A tension torsion strap is connected at one end to the housing and is connected at its other end to the blade root fitting to hold the blade root fitting in the housing when the housing rotates. Coupled between outside walls of the blade root fitting and inside walls of the housing are self lubricating bearings to enable the blade root fitting to rotate within the housing to change the pitch of the tail blades.

Abstract: An aircraft features a nose mounted propeller on a fuselage having a typical helicopter rotor assembly. By reducing the amount of forward thrust needed from the main rotor, the propeller allows greater forward speeds as the angle of attack on the rotor's blades can be kept low to avoid the stalling and violent vibration experienced by conventional helicopters at relatively high speeds. By greatly reducing the amount of thrust produced by the main rotor but still using it to generate lift, the addition of wings can be avoided. The aircraft can be flown in a forward direction in a generally horizontal orientation, as the nose does not have to be pitched downward to create thrust from the main rotor.

Abstract: An airframe (1a) having a main body (4) and a tail body, a main rotor (6) disposed above the main body (4) and driven by an engine inside the airframe (1a), and a tail rotor disposed in a rear part of the tail body (5) are provided. A pair of support legs (8, 8) at left and right sides extending downward from left and right sides in a lower part of the main body (4) and a pair of skids (9) on left and right sides provided on the lower ends of the support legs (8) and positioned out of the main body (4) in the width direction of the airframe (1a) in a front view are provided. A radiator (71) at a position more frontward than the front ends of the skids (9) in a side view, formed extendedly downward from the vicinity of a bottom surface (83) of the front part of the main body, and having wind reception surfaces oriented to the longitudinal direction of the airframe is provided.

Abstract: A rotor for a helicopter, having a drive shaft rotating about a first axis; a hub angularly integral with the drive shaft about the first axis; and at least two blades projecting from the hub, on the opposite side to the first axis, and extending along respective second axes crosswise to the first axis; each blade is movable with respect to the hub and the other blades about a respective fourth axis parallel to the first axis, about the respective second axis, and about a respective third axis crosswise to the first and respective second axis; the rotor also has a number of first dampers for damping vibration associated with at least oscillation of the relative blades about the respective fourth axes; the first dampers are connected to one another and each to a relative blade; and, in a radial direction with respect to the first axis, at least one first damper is located between the first axis and the fourth axis of the relative blade.

Abstract: A helicopter capable of preventing an increase in size of an airframe and achieving high-speed flight is provided. Provided is an airframe for supporting a main rotor so as to be rotatable, a propeller having a plane of rotation intersecting a plane of rotation of the main rotor, a propeller supporting portion that supports the propeller so as to be movable between positions behind and at the side of the airframe, and a tail disposed on the airframe, having a surface intersecting the plane of rotation of the main rotor.

Abstract: A transmission gearbox for a rotary-wing aircraft includes a main gearbox and a variable speed gearbox in meshing engagement with the main rotor gearbox. The variable speed gearbox permits at least two different RPMs for the main rotor system without disengaging the engine(s) or changing engine RPMs. The variable speed gearbox includes a clutch, preferably a multi-plate clutch, and a freewheel unit for each engine. A gear path drives the main gearbox in a “high rotor speed mode” when the clutch is engaged to drive the main rotor system at high rotor rpm for hover flight profile. A reduced gear path drives the main gearbox in a “low rotor speed mode” when the clutch is disengaged and power is transferred through the freewheel unit, to drive the main rotor system at lower rotor rpm for high speed flight. The variable speed gearbox may be configured for a tail drive system that operates at a continuous speed, a tail drive system that changes speed with the main rotor shaft or for no tail drive system.

Abstract: A rotor for a helicopter, the rotor having a drive shaft rotating about a first axis; a hub connected functionally to the drive shaft in angularly fixed manner with respect to the first axis and in rotary manner with respect to a second axis crosswise to the first axis; and two blades connected to the hub in angularly fixed manner with respect to the first and second axis and in rotary manner with respect to respective third axes; the rotor also having supporting means for supporting the blades with respect to the hub in rotary manner about the respective third axes; the supporting means having at least one supporting member made at least partly of elastomeric material and interposed between a first surface and a second surface integral with a respective blade and the hub respectively; and the supporting member deforming, in use, to permit rotation of the blade, with respect to the hub, about the respective third axis. (FIG.

Abstract: A torque resisting device for a helicopter which comprises a body, a first rotor and a tail rotor wherein the device comprises a deflector secured to and moveable relative to the body, wherein the deflector is positioned between the main rotor and the tail rotor and wherein the deflector is positioned generally aligned with the body in a non-deployed position and a portion of the deflector is positioned spaced apart from the body in a deployed position. Additionally, a method to counteract torque in the operating of a helicopter.

Abstract: This disclosure involves aerial robots that dispenses conductive filament or systems, methods, and software for support such aerial robots. One remotely powered aerial robot system includes an aerial robot and a power source. The aerial robot comprises a body, a first propeller coupled to the body and operable to provide thrust to the aerial robot, a rotatable spool coupled to the body, and a conductive filament that is dispensed from the spool by rotation of the spool is one direction and retrieved by rotation of the spool in another direction. The power source is coupled with, and remote from, the aerial robot via the conductive filament, where the conductive filament is operable to power the first propeller using power from the power source.

Abstract: A control system and method of producing a stabilizing feedback includes generating a control output with a link in response to a deflection of a structure, the control output operable to at least partially resist the deflection.

Abstract: A helicopter has at least one main rotor (2) situated on an airframe (1), on which a tail rotor (4) is additionally attached spaced apart from the airframe (1) via a tail boom (3) for torque equalization. The tail boom (3) is provided with elements for the aerodynamic support of the torque equalization, which include at least one auxiliary wing (5a, 5b), extending along the tail boom (3) on the side facing away from the main rotor rotational direction, for flow acceleration of the exhaust air of the main rotor (2) passing this area.

Abstract: A dual, coaxial rotor helicopter is provided that is relatively easy to fly. Thrust is provided by two ducted fans that are mounted at the rear of the aircraft and spaced apart laterally. Differential thrust generated by the fans provides yaw control for the aircraft, and forward thrust is provided by the fans working in combination. The coaxial rotors are preferably utilized primarily for lift, and not for forward thrust, which simplifies the control requirements. The coaxial rotor with ducted fan configuration also results in lower vibratory loads being imposed on the helicopter, thereby increasing its speed capability. The fan ducts serve to protect the fans, augment the fan thrust at low airspeeds, increase the efficiency of the fans at cruise speeds, and provide horizontal and vertical stabilizing surfaces to ensure aircraft flight stability.

Abstract: A helicopter (2) comprising a body portion (4), a plurality of rotor blades (6) which are mounted for rotation with respect to the body portion (4), and a fan (8) which is mounted for rotation in an opposite direction to the direction of rotation of the rotors (6), the rotor blades (6) being such that they are spaced apart in a vertical direction, and the fan (8) being such that when it rotates it generates a torque which acts to counteract at least a part of the torque generated by the rotor blades (6) when they rotate.

Abstract: An aerial robot is disclosed. The aerial robot may include at least one pair of counter-rotating blades or propellers, which may be contained within a circumferential shroud or a duct. In one embodiment, the aerial robot may have the ability to hover and move indefinitely. Electric power to the robot may be provided by a tether or an on-board power supply. In tethered embodiments, a solid-state, electronic voltage transformer may be used to reduce a high voltage, low current source to lower voltage, higher current source. In one embodiment, secure data communication between a ground unit and the aerial robot is facilitated by impressing high bandwidth serial data onto the high voltage tether wires or a thin optical fiber which is co-aligned with the tether wires. In one embodiment, precise navigational and position controls, even under extreme wind loads, are facilitated by an on-board GPS unit and optical digital signal processors.

Abstract: A ducted fan for a helicopter includes a transverse duct and a counter-torque device supported within the duct. The counter-torque device includes a rotor rotatably mounted within the duct and a stator fixedly mounted within the duct downstream from the rotor. The rotor includes a rotor hub having a rotor axis, and rotor blades extending from the hub. The Rotor blades have a modulated angular distribution about the rotor axis. The stator includes a stator hub, and a plurality of stator vanes distributed around the stator hub. The stator vanes are angularly modulated around the stator hub.