Abstract: A system for determining a health status of a positive temperature coefficient resistor (PTCR) heater assembly includes a PTCR heater assembly and a health monitoring system. An input voltage is provided to the PTCR heater assembly to provide heating. The health monitoring system includes a first sensor configured to sense the input voltage at the PTCR heater assembly and a second sensor configured to sense a current through the PTCR heater assembly. The health monitoring system is configured to determine a baseline characteristic and an observed characteristic each relating to an inrush peak of the PTCR heater assembly and based on the input voltage and the current. The health monitoring system compares the observed characteristic to the baseline characteristic to assess a health status of the PTCR heater assembly and outputs the health status for PTCR heater assembly diagnostics and/or prognostics.

Abstract: An angle of attack sensor includes a vane assembly and a multi-piece faceplate adjacent the vane assembly. The faceplate includes a heated chassis defining a pocket and a mounting plate positioned adjacent the heated chassis and having an opening. The vane assembly has a portion that is positioned in the pocket of the heated chassis and extends through the opening of the mounting plate.

Abstract: An angle of attack sensor includes a housing having an open end and a closed end, a faceplate positioned on the open end of the housing, the faceplate comprising a periphery at an outer edge of the faceplate, a central opening, and an exterior surface extending from the periphery to the central opening, and a vane assembly extending through the central opening of the faceplate. The exterior surface of the faceplate has a sloped profile from the periphery to the central opening.

Abstract: An angle of attack sensor includes a housing having an open end and a closed end. A faceplate is positioned on the open end of the housing. The faceplate comprises an integral bearing support cage that extends into the housing and is configured to accept a first bearing and a second bearing, a periphery at an outer edge of the faceplate, a central opening, and an exterior surface extending from the periphery to the central opening. A vane assembly extends through the central opening of the faceplate. A vane shaft extends into the housing and is connected to the vane assembly, and a rotational position sensor is connected to the vane shaft.

Abstract: An apparatus and method for inspecting articles incorporating positive temperature coefficient resistors. The inspection apparatus includes a computing device, a power source, a housing, a support, and a thermal imager, each mounted within an interior volume of the housing. The inspection method includes receiving a first thermal image of the unpowered article mounted within the support and receiving a second thermal image of the powered article after an optimized time delay. The method further includes outputting a health indication of the positive temperature coefficient resistors based on a comparison of the first thermal image and the second thermal image.

Abstract: A system for determining a health status of a positive temperature coefficient resistor (PTCR) heater assembly includes a PTCR heater assembly and a health monitoring system. An input voltage is provided to the PTCR heater assembly to provide heating. The health monitoring system includes a first sensor configured to sense the input voltage at the PTCR heater assembly and a second sensor configured to sense a current through the PTCR heater assembly. The health monitoring system is configured to determine a baseline characteristic and an observed characteristic each relating to an inrush peak of the PTCR heater assembly and based on the input voltage and the current. The health monitoring system compares the observed characteristic to the baseline characteristic to assess a health status of the PTCR heater assembly and outputs the health status for PTCR heater assembly diagnostics and/or prognostics.

Abstract: A methodology includes circulating a temperature-controlled and flow-rate-controlled medium through a container at a controlled flow rate and submerging a thermistor with the medium. With the thermistor submerged, a power output of the thermistor is determined and compared to a power criterion, after which classification of the thermistor occurs based on a comparison of the power output to the power criterion. The methodology can include submerging a reference thermistor within the medium and determining a reference power output of the reference thermistor with the reference thermistor submerged within the medium, the power criterion determined based on the reference power output.

Abstract: An angle of attack sensor includes a vane assembly and a multi-piece faceplate adjacent the vane assembly. The faceplate includes a heated chassis defining a pocket and a mounting plate positioned adjacent the heated chassis and having an opening. The vane assembly has a portion that is positioned in the pocket of the heated chassis and extends through the opening of the mounting plate.

Abstract: An angle of attack sensor includes a vane assembly and a multi-piece faceplate adjacent the vane assembly. The faceplate includes a heated chassis defining a pocket and a mounting plate positioned adjacent the heated chassis and having an opening. The vane assembly has a portion that is positioned in the pocket of the heated chassis and extends through the opening of the mounting plate.

Abstract: An angle of attack sensor includes a housing having an open end and a closed end, a faceplate positioned on the open end of the housing, the faceplate having an opening, a vane assembly extending through the opening of the faceplate, a vane shaft connected to the vane assembly and extending within the housing, the vane shaft having a bore extending through the vane shaft, a bearing surrounding the vane shaft, a vane shaft seal surrounding the vane shaft adjacent the bearing, and a first vent hole extending from an interior surface of the vane shaft to an exterior surface of the vane shaft between the bearing and a first end of the vane shaft seal, the first vent hole being in fluid communication with the bore of the vane shaft.

Abstract: A damper assembly for an angle of attack sensor includes a rotor including a conical portion, a damper housing in which the rotor is positioned, the damper housing being configured to be adjusted axially with respect to the rotor and including a tapered interior surface that matches a profile of the conical portion, and a locking mechanism adjacent the damper housing.

Abstract: An angle of attack sensor includes a vane assembly and a multi-piece faceplate adjacent the vane assembly. The faceplate includes a mounting plate having an opening and a heated chassis positioned adjacent the mounting plate and having a ring portion extending through the opening, the ring portion defining a ring-shaped deflector that surrounds the vane assembly and extends beyond an exterior surface of the mounting plate.

Abstract: An adjustable moment counterweight assembly for an angle of attack sensor includes a fixed counterweight configured to fixedly attach to a shaft of the angle of attach sensor, the shaft being rotatable about an axis; an adjustable counterweight configured to move in a radial direction relative to the fixed counterweight via rotation of a threaded member; and a first fastener in operable communication with the fixed counterweight and the adjustable counterweight such that the first fastener can fixedly attach the adjustable counterweight to the fixed counterweight.

Abstract: An angle of attack sensor includes a housing having an open end and a closed end, a faceplate positioned on the open end of the housing, the faceplate having an opening, a vane assembly extending through the opening of the faceplate, a vane shaft connected to the vane assembly and extending within the housing, the vane shaft having a bore extending through the vane shaft, a bearing surrounding the vane shaft, a vane shaft seal surrounding the vane shaft adjacent the bearing, and a first vent hole extending from an interior surface of the vane shaft to an exterior surface of the vane shaft between the bearing and a first end of the vane shaft seal, the first vent hole being in fluid communication with the bore of the vane shaft.

Abstract: An adjustable moment counterweight assembly for an angle of attack sensor includes a fixed counterweight configured to fixedly attach to a shaft of the angle of attach sensor, the shaft being rotatable about an axis; an adjustable counterweight configured to move in a radial direction relative to the fixed counterweight via rotation of a threaded member; and a first fastener in operable communication with the fixed counterweight and the adjustable counterweight such that the first fastener can fixedly attach the adjustable counterweight to the fixed counterweight.

Abstract: An angle of attack sensor includes a housing, a heated chassis positioned at least partially within the housing and defining a pocket, a mounting plate positioned adjacent the heated chassis and having a circular opening, an external surface facing away from the housing, and an internal surface facing toward the housing, and a vane assembly extending through the circular opening of the mounting plate. The vane assembly includes a vane extending from a root to a tip and a vane base connected to the root of the vane and positioned within the pocket of the heated chassis such that the vane base is offset inwardly from the external surface toward the housing.

Abstract: An angle of attack sensor includes a vane that is freely rotatable to align with a direction of an oncoming airflow over the vane. The airfoil includes a root proximate a vane hub that connects to a rotatable shaft, a tip opposite the root, a leading edge, a trailing edge opposite the leading edge, a first lateral face, a second lateral face, and a heating element disposed within the airfoil between the first and second lateral faces proximate the leading edge. The first lateral face extends from the leading edge to the trailing edge. The second lateral face is opposite the first lateral face and extends from the leading edge to the trailing edge. The first and second lateral faces are symmetric about a chord of the airfoil and each have an outer surface profile that is nonlinear and geometrically convex from the leading edge to the trailing edge.

Abstract: A damper assembly for an angle of attack sensor includes a rotor including a conical portion, a damper housing in which the rotor is positioned, the damper housing being configured to be adjusted axially with respect to the rotor and including a tapered interior surface that matches a profile of the conical portion, and a locking mechanism adjacent the damper housing.

Abstract: An angle of attack sensor includes a vane assembly and a multi-piece faceplate adjacent the vane assembly. The faceplate includes a mounting plate having an opening and a heated chassis positioned adjacent the mounting plate and having a ring portion extending through the opening, the ring portion defining a ring-shaped deflector that surrounds the vane assembly and extends beyond an exterior surface of the mounting plate.

Abstract: The bearings of aircraft angle of attack (AOA) vanes are susceptible to lightning strike damage, which causes fluting on the inner and outer races of the bearings and causes the bearings to generate friction, noise, and vibrations. To prevent the bearings from experiencing damage due to lightning strikes, the bearings, the shaft, and/or the mounting plate are configured to create an electric isolator to prevent the electric current from the lightning strike from passing through the bearings, thereby preventing the bearings from incurring lightning strike damage.