A blade angle feedback assembly for an aircraft-bladed rotor, the rotor rotatable about a longitudinal axis and having an adjustable blade pitch angle, is provided. The assembly comprises a feedback device coupled to rotate with the rotor and to move along the longitudinal axis with adjustment of the blade pitch angle, the feedback device comprising a plurality of position markers circumferentially spaced around the feedback device, a plurality of sensors positioned adjacent the feedback device and each configured for producing a sensor signal in response to detecting passage of the position markers as the feedback device rotates about the longitudinal axis, the sensors circumferentially spaced around the feedback device and axially offset along the longitudinal axis, and a control unit communicatively coupled to the sensors and configured to generate a feedback signal indicative of the blade pitch angle in response to the sensor signals received from the sensors.

Methods and systems for validating a propeller control unit associated with a propeller having blades are provided. Actuation of a control valve of the propeller control unit is commanded to alter a pitch angle of the blades. One of an actual pitch angle of the blades and an actual rotational speed of the propeller is determined after a predetermined time delay has elapsed. The one of the actual pitch angle of the blades and the actual rotational speed of the propeller is compared to a corresponding one of a pitch angle threshold and a rotational speed threshold, the pitch angle threshold and the rotational speed threshold based on a commanded pitch angle. A warning signal is issued in response to determining one of the actual pitch angle failing to meet the pitch angle threshold and the actual rotational speed failing to meet the rotational speed threshold.

A phonic wheel having a body and a tooth is disclosed. An embodiment of the phonic wheel includes a body that is configured to rotate about a rotation axis. The tooth is attached to the body. The tooth has a first axial end relative to the rotation axis, a second axial end opposite the first axial end, and a mid portion extending between the first and second axial ends. The mid portion has a substantially axially uniform height from the body. The first axial end has a greater height from the body than the height of the mid portion.

The invention relates to a method for controlling a pitch angle of the vanes or blades of a propellant body of a turbine engine, comprising generating a pitch command (i.sub.final) according to a rotational speed of the propeller (XN.sub.mes) and a speed setpoint (XN.sub.cons), the method comprises a nominal regulating chain (13), wherein the pitch command is further generated according to a value of a pitch angle (βmes) of the vanes or blades of the propellant body, and an off-nominal regulating chain (16), wherein the pitch command is generated independently of a value of a pitch angle of the vanes or blades of the propellant body.

A propeller control system for controlling a blade pitch angle including: a propeller blade extending from a blade base, the propeller blade being configured to rotate around a longitudinal axis to generate thrust for the propeller blade and rotate around a pitch change axis to adjust the blade pitch angle, wherein the pitch change axis extends through a center point of the blade base; a trunnion pin operably connected to the blade base at a location offset from the center point; a yoke plate operably connected to the trunnion pin; an actuator configured to move the yoke plate linearly along the longitudinal axis to rotate the trunnion pin and the propeller blade around the pitch change axis; and a transfer tube operably connected to the yoke plate, the transfer tube being free to rotate around the longitudinal axis as the actuator moves the yoke plate linearly along the longitudinal axis.

A blade angle feedback system for an aircraft-bladed rotor rotatable about a longitudinal axis and having an adjustable blade pitch angle is provided. A feedback device is coupled to rotate with the rotor and to move along the axis with adjustment of the blade angle. At least one position marker is affixed to a core of the feedback device and extends along a direction angled relative to the axis. The core is made of a first material having a first magnetic permeability and the position marker comprises a second material having a second magnetic permeability greater than the first magnetic permeability. A sensor is positioned adjacent the feedback device and produces, as the feedback device rotates about the axis, a sensor signal in response to detecting passage of the position marker. A control unit generates a feedback signal indicative of the blade angle in response to the sensor signal.

A blade angle feedback assembly for a variable-pitch rotor of an aircraft engine, the rotor rotatable about an axis and having rotor blades rotatable about respective spanwise axes to adjust a blade angle thereof, is provided. A sensor is configured to provide feedback on the blade angle of the rotor blades by detecting a relative movement between the sensor and a feedback device having at least one position marker thereon. The sensor comprises a magnet having a magnetic field and a first pole and a second pole opposite the first pole. A magnetic shield is configured to define a magnetic return path for at least a portion of a magnetic flux of the magnetic field exiting from the first pole of the magnet toward the second pole, the magnetic shield comprising at least one wall member spanning a distance of relative displacement between the feedback device and the sensor.

Low latency pitch adjustable rotors are disclosed. A disclosed example rotor includes a rotor hub to rotate about a rotational axis, rotor blades coupled to the rotor hub, the rotor blades being pitch adjustable and having corresponding pitch angles, and a reaction hinge operatively coupled between the rotor hub and the rotor blades, the reaction hinge to move relative to the rotor hub in response to an angular acceleration or deceleration of the rotor hub to adjust the pitch angles.

There is provided a blade angle feedback assembly for an aircraft-bladed rotor rotatable about a longitudinal axis and having an adjustable blade pitch angle. The assembly comprises a feedback device coupled to rotate with the rotor, the feedback device having a root surface having a first edge, first position markers extending from the root surface and oriented substantially parallel to the axis, the first position markers circumferentially spaced from one another, at least one second position marker extending from the root surface and positioned between two adjacent first position markers at an angle thereto, the at least one second position marker having an end positioned adjacent to the first edge and non-flush therewith, and at least one sensor mounted adjacent the feedback device and configured to detect a passage of the first position markers and the at least one second position marker as the feedback device rotates about the axis.

There is provided a pitch control assembly for a rotor of an aircraft, the rotor rotatable about a longitudinal axis and having blades each rotatable about a span-wise axis to adjust a blade pitch angle thereof, the assembly comprising a plurality of position markers spaced circumferentially around the longitudinal axis and having lengths along the longitudinal axis which vary monotonically and incrementally, at least one sensor configured for producing at least one sensor signal in response to detecting a relative movement between the plurality of position markers and the at least one sensor, and a control unit communicatively coupled to the at least one sensor and configured to generate a feedback signal indicative of the blade pitch angle in response to the at least one sensor signal received from the at least one sensor.