Abstract: Methods and systems for measuring an axial position of a rotating component of an engine are described herein. The method comprises obtaining a signal from a sensor coupled to the rotating component, the rotating component having a plurality of position markers distributed about a surface thereof, the position markers having an axially varying characteristic configured to cause a change in a varying parameter of the signal as a function of the axial position of the rotating component. Based on the signal, the method comprises determining a rotational speed of the rotating component from the signal, determining the varying parameter of the signal, and finding the axial position of the rotating component based on a known relationship between the axial position, the rotational speed, and the varying parameter of the signal.

Abstract: There is provided a blade angle feedback assembly for a propeller of an aircraft engine. The propeller is rotatable about an axis and has propeller blades rotatable about respective spanwise axes to adjust a blade angle thereof. The blade angle feedback assembly comprises a feedback ring having a plurality of position markers disposed thereon, at least one sensor configured to provide feedback on the blade angle of the propeller blades by detecting a relative movement between the feedback ring and the at least one sensor, and at least one shielding element provided between the feedback ring and the propeller, the at least one shielding element configured to shield the feedback ring from electromagnetism.

Abstract: Methods and systems for testing a sensor of a propeller blade angle position feedback system are described. A sensor signal is received from a sensor at a known position relative to a feedback device, the feedback comprising a ring and at least one pair of position markers spaced from one another around a circumference thereof, the sensor configured for successively detecting passage of the position markers as the feedback device rotates at a known rotational speed and an axial distance between the sensor and the feedback device varies. From the sensor signal a measured position of the sensor relative to the feedback device and a measured rotational speed of the feedback device are determined. The measured position and the measured rotational speed are compared to the known position and the known rotational speed to determine a sensor accuracy.

Abstract: 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.

Abstract: Methods and systems for measuring an axial position of a rotating component of an engine are described herein. The method comprises obtaining a signal from a sensor coupled to the rotating component, the rotating component having a plurality of position markers distributed about a surface thereof, the position markers having an axially varying characteristic configured to cause a change in a varying parameter of the signal as a function of the axial position of the rotating component. Based on the signal, the method comprises determining a rotational speed of the rotating component from the signal, determining the varying parameter of the signal, and finding the axial position of the rotating component based on a known relationship between the axial position, the rotational speed, and the varying parameter of the signal.

Abstract: Methods and systems for measuring an axial position of a rotating component of an engine are described herein. The method comprises obtaining a signal from a sensor coupled to the rotating component, the rotating component having a plurality of position markers distributed about a surface thereof, the position markers having an axially varying characteristic configured to cause a change in a varying parameter of the signal as a function of the axial position of the rotating component. Based on the signal, the method comprises determining a rotational speed of the rotating component from the signal, determining the varying parameter of the signal, and finding the axial position of the rotating component based on a known relationship between the axial position, the rotational speed, and the varying parameter of the signal.

Abstract: A sensor signal comprising a first signal pulse having a first voltage amplitude and a second signal pulse having a second voltage amplitude greater than or substantially equal to the first voltage amplitude is obtained from a sensor positioned adjacent a feedback device coupled to rotate with an aircraft-bladed rotor about a longitudinal axis and to move along the axis with adjustment of the rotor's blade pitch angle. The feedback device comprises a reference feature configured to generate the second signal pulse and varying detectable feature(s) configured to generate the first signal pulse and to cause a change in the first voltage amplitude as a function of an axial position of the feedback device along the axis. A voltage ratio is determined based on the first voltage amplitude and the second voltage amplitude, and the axial position of the feedback device is determined from the voltage ratio.

Abstract: Methods and systems for testing a sensor of a propeller blade angle position feedback system are described. A sensor signal is received from a sensor at a known position relative to a feedback device, the feedback comprising a ring and at least one pair of position markers spaced from one another around a circumference thereof, the sensor configured for successively detecting passage of the position markers as the feedback device rotates at a known rotational speed and an axial distance between the sensor and the feedback device varies. From the sensor signal a measured position of the sensor relative to the feedback device and a measured rotational speed of the feedback device are determined. The measured position and the measured rotational speed are compared to the known position and the known rotational speed to determine a sensor accuracy.

Abstract: The test rig can be used for testing a blade pitch measurement system of a variable pitch propeller system. The test rig can include a first mount rotatably mounted to the frame and configured to receive the feedback device, a rotation motor drivingly coupled to rotate the ring mount relative to the frame around a rotation axis, a second mount configured to receive the pitch sensor, a mechanism configured for moving the second mount along an orientation parallel to the rotation axis, and a controller configured to control the rotation of the rotation motor to a variable rotation speed, and for controlling the movement of the second mount to variable positions via the mechanism.

Abstract: An aircraft propeller control system for an aircraft propeller with adjustable blade angle has a blade angle feedback ring and a sensor, one of which is mounted for rotation with the propeller. The blade angle feedback ring moves longitudinally along with adjustment of the blade angle and has position markers circumferentially spaced apart at distances that vary along a longitudinal axis. The sensor is positioned adjacent the feedback ring for producing signals indicative of passage of the position markers. Intervals between signals are indicative of circumferential distances between position markers. A controller measures longitudinal position of the feedback ring based on the intervals and is configured to produce a warning signal if the longitudinal position is outside a first threshold range.

Abstract: A propeller control system for an aircraft propeller rotatable about a longitudinal axis and having an adjustable blade angle is provided. A blade angle feedback ring is coupled to the propeller to rotate with the propeller and to move along the longitudinal axis along with adjustment of the blade angle. The feedback ring includes position markers spaced around its circumference. A sensor is positioned adjacent the feedback ring for producing signals indicative of passage of the position markers. A controller is in communication with the sensor, and is configured for: measuring a distance between the position markers, wherein the distance is representative of a longitudinal position of the feedback ring; determining whether a value representative of the longitudinal position is within a first threshold range; and when the value is within the first threshold range, storing the value as a calibration value associated with the blade angle feedback ring.

Abstract: There is provided a blade angle feedback assembly for a propeller of an aircraft engine. The propeller is rotatable about an axis and has propeller blades rotatable about respective spanwise axes to adjust a blade angle thereof. The blade angle feedback assembly comprises a feedback ring having a plurality of position markers disposed thereon, at least one sensor configured to provide feedback on the blade angle of the propeller blades by detecting a relative movement between the feedback ring and the at least one sensor, and at least one shielding element provided between the feedback ring and the propeller, the at least one shielding element configured to shield the feedback ring from electromagnetism.

Abstract: A blade angle feedback ring assembly for an aircraft propeller rotatable about a longitudinal axis and having an adjustable blade angle is provided. A feedback ring is coupled to the propeller to rotate therewith and to move along a longitudinal axis with adjustment of the blade angle. A plurality of rods are coupled to the feedback ring and extending along a direction substantially parallel to the longitudinal axis, the rods configured to support the feedback ring for longitudinal sliding movement along the longitudinal axis with adjustment of the blade angle. At least one shielding element is provided between the feedback ring and the propeller for shielding the feedback ring from electromagnetism.

Abstract: A sensor signal comprising a first signal pulse having a first voltage amplitude and a second signal pulse having a second voltage amplitude greater than or substantially equal to the first voltage amplitude is obtained from a sensor positioned adjacent a feedback device coupled to rotate with an aircraft-bladed rotor about a longitudinal axis and to move along the axis with adjustment of the rotor's blade pitch angle. The feedback device comprises a reference feature configured to generate the second signal pulse and varying detectable feature(s) configured to generate the first signal pulse and to cause a change in the first voltage amplitude as a function of an axial position of the feedback device along the axis. A voltage ratio is determined based on the first voltage amplitude and the second voltage amplitude, and the axial position of the feedback device is determined from the voltage ratio.

Abstract: Methods and systems for measuring an axial position of a rotating component of an engine are described herein. The method comprises obtaining a signal from a sensor coupled to the rotating component, the rotating component having a plurality of position markers distributed about a surface thereof, the position markers having an axially varying characteristic configured to cause a change in a varying parameter of the signal as a function of the axial position of the rotating component. Based on the signal, the method comprises determining a rotational speed of the rotating component from the signal, determining the varying parameter of the signal, and finding the axial position of the rotating component based on a known relationship between the axial position, the rotational speed, and the varying parameter of the signal.

Abstract: 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.

Abstract: Systems and methods for controlling a crossing threshold used in determining a rotational speed of a propeller of an aircraft engine. An initial value for the crossing threshold is set. A sensor signal is received that comprises a first series of pulses indicative of passage of position markers about a circumference of a propeller shaft. A detection signal is generated that comprises a second series of pulses indicative of within the first series of pulses that have a zero-crossing transition and a magnitude that exceeds the crossing threshold. The rotational speed of the propeller is determined from the detection signal. The crossing threshold is adjusted as a function of the rotational speed.

Abstract: Herein provided is a phonic wheel for use in a gas turbine engine and associated systems and methods. The phonic wheel comprises a circular disk having first and second opposing faces. The circular disk defines a root surface that extends between and circumscribes the first and second faces. A first plurality of projections extend from the root surface and are oriented substantially parallel to an axis of rotation of the disk. The first plurality of projections are circumferentially spaced substantially equally from one another and each have a first physical configuration. At least one second projection extends from the root surface and is positioned between two adjacent first projections, the at least one second projection having a second physical configuration different from the first physical configuration.

Abstract: Herein provided are systems and methods for synchrophasing multi-engine aircraft. A phonic wheel is coupled to a first propeller of a first engine of the aircraft. A sensor is disposed and configured for producing a signal in response to passage of first and second position markers on the phonic wheel. A control system is communicatively coupled to the sensor for obtaining the signal, and configured for: determining an expected delay between two subsequent signal pulses of the signal; identifying from within the plurality of signal pulses a particular pulse associated with the second position marker; determining, based on a particular time at which the particular pulse associated with the second position marker was produced, that a rotational position of the first propeller corresponds to a reference position at the particular time; and performing at least one synchrophasing operation for the aircraft based on the rotational position of the first propeller.

Abstract: A propeller control system for an aircraft propeller rotatable about a longitudinal axis and having an adjustable blade angle is provided. A blade angle feedback ring is coupled to the propeller to rotate with the propeller and to move along the longitudinal axis along with adjustment of the blade angle. The feedback ring includes position markers spaced around its circumference. A sensor is positioned adjacent the feedback ring for producing signals indicative of passage of the position markers. A controller is in communication with the sensor, and is configured for: measuring a distance between the position markers, wherein the distance is representative of a longitudinal position of the feedback ring; determining whether a value representative of the longitudinal position is within a first threshold range; and when the value is within the first threshold range, storing the value as a calibration value associated with the blade angle feedback ring.