Abstract: A method for operating a control valve using an HVAC actuator is described, the method comprises a circuit of the HVAC actuator executing the steps of: monitoring (S1) a rotation angle (?) associated with a drive torque (Mdrive) applied by the HVAC actuator for moving the valve member; detecting (S2) a blocking of the control valve, if the applied drive torque (Mdrive) effects a change of the rotation angle (??) which is smaller than a threshold angle (?th); upon detection of the blocking, controlling the HVAC actuator to repeatedly change the applied drive torque (Mdrive) between a first torque value (M1) and a second torque value (M2); and controlling the HVAC actuator to periodically modulate (S4) the first torque value (M1) between a third torque value and a fourth torque.

Abstract: A thrust control assembly includes a balk application arrangement which provides, in response to a received balk command to prohibit command of thrust in a balk direction, a balk force on a rotatable thrust lever acting to oppose an attempt by the pilot to move the lever in a direction so as to command or increase thrust in the balk direction. The balk application arrangement controls an auto-throttle actuator to provide the balk force on the thrust lever.

Abstract: A passive gust load alleviation device for an aerodynamic panel includes a free-floating aerodynamic control surface connected to the panel via a revolute joint. A counterweight is connected to the control surface. Relative to a direction of ambient airflow, the counterweight has a center of gravity forward of the axis of rotation. The counterweight is configured to passively deflect the control surface about the axis to alleviate a gust load. A vehicle includes an aerodynamic panel connected to a body and extending into ambient airflow, and the control surface and counterweight. A method for alleviating the gust load on an aircraft panel includes connecting the control panel, via the revolute joint, along a trailing edge of the panel, and during a flight of an aircraft having the panel, passively deflecting the control panel about the axis in response to an incident wind gust.

Abstract: Disclosed is an aircraft and a method of controlling an aircraft. The aircraft comprises a continuous wing assembly extending from port to starboard sides of the aircraft. The aircraft is controlled partially by flexing portions of the wing, and partially or totally by mechanical systems that alter the position of a fuselage with respect to the wing. The fuselage is attached to the wing by a wing/fuselage joint structure that permits at least two mutually orthogonal axes of rotation of the fuselage relative to the wing. The aircraft includes a sensors, a telemetry system linked to a remote server, and a control system for programming flight information and aircraft control instructions and a plurality of actuators responsive to the control system for rotating the fuselage relative to the wing and flexing the wing for controlling the flight of the aircraft in response to instructions from the control system.

Abstract: An airfoil assembly comprising an airplane wing, a spoiler, and a flap for unmanned and high endurance aircraft. The spoiler is located on an upper surface of the airplane wing while the flap is located on a lower surface of the airplane wing. The spoiler and the flap can occupy at least one-third, and up to three-quarters, the chord span of the airplane wing. The spoiler and the flap are both capable of moving upwards and downwards with respect to the airplane wing through their respective frames.

Abstract: An example method of optimizing reverse thrust operation on an aircraft having two or more engines while landing the aircraft is described. The method includes operating the two or more engines on the aircraft in a reverse idle during a landing rollout of the aircraft, responsively causing deployment of a thrust reverser on each of the engines causing a first reverse idle thrust for slowing the aircraft, monitoring each of the engines for failure of deployment of the thrust reverser, and based on detection of a failure of deployment of a respective thrust reverser on one of the engines, operating the one of the engines on the aircraft at a second reverse idle thrust optimized for a direction of an applied thrust of the one of the engines. The second reverse idle thrust is lower than the first reverse idle thrust.

Abstract: An aircraft is described and includes a fuselage, a wing coupled to the fuselage, and a rotor system including a proprotor system and an engine. An interconnect driveshaft gear is configured to communicate mechanical energy between a gearbox and an interconnect driveshaft. An accessory gear is coplanar with and in mechanical communication with the driveshaft gear. A proprotor gear is coplanar with and in mechanical communication with the interconnect driveshaft gear and the accessory gear and communicates mechanical energy to the proprotor system. An engine gear coplanar and in mechanical communication with the interconnect driveshaft ear, the accessory gear, and the proprotor gear transmits mechanical energy to the proprotor system via the proprotor gear.

Abstract: A bimodal propeller aircraft is disclosed. In various embodiments, the aircraft is flown using a cruise propeller and a hover propeller. The hover propeller has one or more folding blades optimized to provide lift to the aircraft in a first flight mode. The cruise propeller is optimized to provide thrust in a second flight mode. In the second flight mode, the one or more folding blades of the hover propeller may remain in a stowed position.

Abstract: A bimodal propeller aircraft is disclosed. In various embodiments, the aircraft is flown using a cruise propeller and a hover propeller. The hover propeller has one or more folding blades optimized to provide lift to the aircraft in a first flight mode. The cruise propeller is optimized to provide thrust in a second flight mode. In the second flight mode, the one or more folding blades of the hover propeller may remain in a stowed position.

Abstract: According to one embodiment, a spring tension adjustment device for adjusting tension in a spring includes a rotation feature and a plurality of spring-attachment features. The rotation feature defines a first axis of rotation. Each spring-attachment feature is configured to receive one end of a spring, each spring-attachment feature being located at a different distance from the rotation feature.

Abstract: A yoke for controlling the attitude of an aircraft is provided. The yoke includes a chassis, a pitch hub, a roll hub, a support column, a control wheel and a connection arrangement. The pitch hub rotatably mounts to the chassis. The roll hub rotatably mounts to the chassis for motion being generally parallel to the pitch hub. The support column attaches to the pitch hub for rotational motion with the pitch hub relative to the chassis. The control wheel pivotally attaches to the support column for rotational motion about a control wheel pivot axis being generally perpendicular to the pitch and roll hubs. The connection arrangement couples the control wheel to the roll hub and is configured to rotate the roll hub about the roll axis when the control wheel is rotated about the control wheel pivot axis. A system including interconnected yokes is also provided.

Abstract: This invention provides an improvement in a control stick (e.g., joystick, side-stick, etc.) (20) adapted to control the movement of an object (e.g., an airfoil surface). The improvement includes: a support (21); an intermediately-pivoted upper member (23) mounted on the support, the upper member having an upper portion (24), and lower portion (25); an intermediate member (26) having an upper portion pivotally connected to the upper member lower portion, and having a lower portion; and a lower member (29) having a lower portion pivotally mounted on the support, and having an upper portion; and wherein the intermediate member lower portion is movably mounted on the lower member such that pivotal movement of the upper member upper portion relative to the support will produce pivotal movement of the intermediate and lower members relative to the support; and a resilient member (31) arranged to bias the direction of relative movement between the intermediate and lower members.

Abstract: The present invention relates to a sensor system for monitoring the synchronism of control surfaces of an aircraft with two transmission links for the mechanical transmission of the movements of one or more control surfaces to at least one sensor, wherein the two transmission links are coupled with each other mechanically and/or via the at least one sensor, whereby a difference between the movements transmitted by the transmission links can be monitored.

Abstract: A redundant electromechanical actuator is provided that includes first and second electric motors, a common output shaft, first and second drive cable drums, first and second driven cable drums, a first cable, and a second cable. The first and second electric motors are each adapted to be controllably energized to supply a drive torque. The common output shaft is coupled to receive the drive torque supplied from one or both of the motors. The first and second drive cable drums are coupled to the common output shaft to receive the drive torque from one or both of the motors. The first and second driven cable drums are each configured, upon being driven, to rotate. The first cable is coupled between the first drive cable drum and the first driven cable drum, and the second cable is coupled between the second drive cable drum and the second driven cable drum.

Abstract: An aircraft flight control system advantageously is provided with a control rod which is spline-connected to a bearing assembly so as to permit simultaneous independent longitudinal and rotational movements of the control rod while isolating such movements from one another (e.g., so as to allow operative interconnection to an aircraft's aileron and elevator control surfaces). Thus, the control rod is moveable in longitudinal and rotational directions relative to a longitudinal axis of the control rod in response to pitch and roll command inputs, respectively. The control rod is splined operatively to the bearing assembly so as to allow for independent simultaneous longitudinal and rotational movements of the control rod relative to the longitudinal axis thereof to thereby allow the command inputs to be transferred to the aircraft's respective flight control surfaces.

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: An aircraft flight control disconnect mechanism between the pilot and co-pilot controls, including a pair of concentrically positioned opposed circular jaws, each jaw having either mating tapered teeth or mating tapered openings, which when the jaws are axially separated, disconnects one pilot control from the other and a rotating control sleeve concentrically aligned with and rotatably attached to one of said jaws, the sleeve including a helical cam slot surrounding a fixed roller whereby rotation of the control sleeve moves the said connected jaw toward or away from the adjacent jaw so that the two jaws are free to rotate independent of each other.

Abstract: In a flap operating system, left and right actuators for operating left and right flaps are synchronized with each other by left and right pulleys and first and second synchronizing cables wound in an X-shape around the left and right pulleys. If one of the hydraulic actuators fall into a free failure or fails due to sticking, a difference is generated between the rotational angles of the left and right pulleys. When the difference exceeds a threshold value, the operations of the left and right actuators are stopped, whereby an excessive load is previously prevented from being applied to a main wing structure or the flap operating system.

Abstract: The apparatus comprises:

Abstract: A surface effect craft of simple construction achieving improved operational stability and performance at various speeds. The craft includes first and second main wing sections merge into the central hull to form a continuous aerodynamic wing structure. The wing structures are very thick with maximum thickness ratio of wing thickness to chord length on the order of 25-30% with the first and second wing sections being swept back, merging into first and second vertical side wall directional stabilizers, the wing shaped structure forming a generally U-shaped rear section (as best viewed from a rear plan or sectional view). The craft preferably includes an aft elevated secondary wing structure extending between the first and second vertical side wall directional stabilizers whereby both the main wing sections and the aft elevated secondary wing structure provide lift.

Abstract: An autogyro aircraft has freewheeling rotor blades that provide lift. A separate pusher propeller provides forward thrust. The rotor system (20) has a collective arm (30) as a control for selectively setting and maintaining a tension force on a collective cable to regulate the rotor blade angle of attack or pitch angle between a no-lift attitude and a positive lift angle. The collective arm (30) sets a tension on collective cable against a coil spring biasing. The collective arm is connected to pivot or tilt a pitch change horn assembly and, in turn, connected rotor blades. The collective arm can be selectively set and maintained and released and reset both on the ground and in flight.

Abstract: A flight control apparatus for use in an aircraft includes support structure for suspending a pilot beneath a pair of wings while permitting movement of the pilot relative to the aircraft in the forward, rearward and both lateral directions. A control system is connected between the support structure and the wings for altering the geometries of the wings during flight to vary the drag and lift characteristics of the wings and alter the direction of flight and the speed/performance range of the aircraft in response to movement of the pilot relative to the aircraft in any of the forward, rearward, and lateral directions. The geometries of the wings are altered during flight by moving the leading edges between extended and retracted positions relative to the central longitudinal axis of the aircraft in response to movement of the pilot in the forward, rearward and both lateral directions relative to the aircraft.

Abstract: An electrohydraulic actuator system has a first pair of actuators and a control circuit and a control valve for each actuator. The control circuits generate actuator position error signals and are also responsive to divergence of the operating position of the respective valves from a mean valve operating position thereby tending to maintain the valve operating positions, and hence the forces on the actuators, identical. The magnitudes of the position error signals are limited to limit overdrive of the valves in the event of minor malfunctions thereof and to permit a malfunction indication to be provided. The system also includes a further pair of actuators having an associated control circuit which is responsive to a selected differential position of the further actuators, for causing one of these actuators to be driven away from a limiting position of the other actuator until the required position differential is obtained.

Abstract: Helicopter tail rotor control system having a quadrant (18) with two flexible cables (20,22) wrapped around the quadrant surface in opposing directions and each attached to the quadrant at a point (42,60) opposite to initial contact of the cable with the quadrant, and spring extension (44, 62) from each cable passing around a pulley (46) and attached to the quadrant at a point on a radial line with the cable attachment.

Abstract: A control assembly (50) for deployment of aircraft wing flaps is comprised of an input cam mechanism (54), a feedback cam mechanism (56) and a summing lever member (58) operatively interconnecting the cam mechanisms for mechanically summing independent inputs therefrom to yield a mechanical output signal for actuating flap deployment drives, wherein the input cam mechanism is comprised of a cam (64) rotationally operable in response to a command input signal and a cam follower (68) in mating engagement therewith for cammed movement with rotation thereof to provide a first input signal to the summing lever characteristic of a predetermined flap configuration, the feedback cam mechanism is comprised of a cam (94) rotationally operable in response to movement of the flaps and a cam follower (100) in mating engagement therewith for cammed movement in response to movement of the flaps to provide a second input signal to the summing lever characteristic of the existing flap configuration; and further wherein the su

Abstract: There is disclosed a cable control system which utilizes servo-regulation to maintain the desired cable tension. The system regulates cable tension, is self-rigging and is capable of sensing control cable failure to prevent runaway regulation.