Abstract: A multi-zone anti-icing system for an aircraft part. The system includes at least two or more-part zones configured with the aircraft part and an electrothermal heater associated with at least one part zone of the aircraft part; at least one resistive temperature detector (RTD) associated with each part zone of the aircraft part configured to generate temperature data associated with each part zone. A controller coupled to the electrothermal heater and configured to implement an algorithm of a control logic for an anti-icing operation that uses feedback temperature data from at least one RTD at an associated part zone wherein the feedback temperature data is analyzed by the controller via the algorithm to assess reliability of the temperature data generated by the at least one RTD associated with each part zone.

Abstract: A system is provided for dispersing supercooled liquid water in an icing wind tunnel. The system includes a spray bar; a spray nozzle coupled to the spray bar; a pressure control valve coupled to the spray bar; and a controller coupled to the pressure control valve and the spray nozzle. The controller is configured to receive input identifying a selected liquid water content and a selected water droplet size for dispersing the supercooled liquid water in the icing wind tunnel; configure an injector duty cycle of the spray nozzle to generate the selected liquid water content; and configure the pressure control valve to generate the selected water droplet size, wherein configuring the spray nozzle and the pressure control valve disperses the supercooled liquid water in the icing wind tunnel.

Abstract: Pendulum dampers are described. The pendulum dampers include a damper body having a first end and a second end, with an axial direction defined between the first end and the second end with a heater bore passing through the damper body in the axial direction from a tail port at the second end toward the first end and a cartridge heater installed within the heater bore, the cartridge heater configured to generate heat and heat a material of the damper body.

Abstract: During a de-ice process, heating zones associated with a rotor may be supplied with power for shedding accreted ice from the heating zone. Priority heating zones associated with the leading edge of the rotor are supplied with power to activate the priority heating zones multiple times during the de-ice process. Heating zones associated with a lower surface of the rotor may be activated after the priority heating zones are first activated. A first dwell may be waited, to allow additional ice accretion on the priority zones. The priority heating zones may then be reactivated after the first dwell. Heating zones associated with an upper surface of the rotor may be then be activated. A second dwell may be waited, to allow additional ice accretion on the priority zones. The de-ice process may then repeat.

Abstract: An ice protection system may comprise an electrical heating mat of an electrically resistive material, wherein the electrically resistive material defines at a first spanwise zone and a first chordwise zone, wherein at least one of the first spanwise zone or the first chordwise zone include a first busbar portion contiguous with the electrically resistive material.

Abstract: An ice protection system for controlling icing on an aircraft surface includes an OAT sensor configured to provide a signal indicative of an OAT, a LWC detector configured to provide a signal indicative of a LWC, an electrothermal device located on the aircraft surface, and an electronic control system configured to determine a critical temperature (TC) at or below which an anti-icing system will be used to preheat the aircraft surface, supply an electrical power having a calculated power level to the electrothermal device, and calculate the power level as being: zero if OAT>TC and LWC=0, controlled based on OAT and LWC if OAT>TC and LWC>0, controlled based on OAT and LWC if OAT<TC and LWC>0, and controlled based on OAT if OAT<TC and LWC=0.

Abstract: An ice protection system for controlling icing on an aircraft surface includes an OAT sensor configured to provide a signal indicative of an OAT, a LWC detector configured to provide a signal indicative of a LWC, an electrothermal device located on the aircraft surface, and an electronic control system configured to determine a critical temperature (TC) at or below which an anti-icing system will be used to preheat the aircraft surface, supply an electrical power having a calculated power level to the electrothermal device, and calculate the power level as being: zero if OAT>TC and LWC=0, controlled based on OAT and LWC if OAT>TC and LWC>0, controlled based on OAT and LWC if OAT<TC and LWC>0, and controlled based on OAT if OAT<TC and LWC=0.

Abstract: An aircraft electrical appliance is provided with a ground-fault-interruption device (50) for protecting it in the event of problematic current loss due to, for example, a compromise in electrical insulation. The device (50) has a GFI circuit (60) comprising a current differential determiner (70), a trigger (80) that is activated upon the current differential corresponding to ground-fault situation, and an interrupter (90) that interrupts power supply to the appliance upon the trigger (80) being activated. The GFI circuit (60) is electrically independent of electrical controller components of the appliance, thereby avoiding expensive software configuration and confirmation.

Abstract: An aircraft electrical appliance is provided with a ground-fault-interruption device (50) for protecting it in the event of problematic current loss due to, for example, a compromise in electrical insulation. The device (50) has a GFI circuit (60) comprising a current differential determiner (70), a trigger (80) that is activated upon the current differential corresponding to ground-fault situation, and an interrupter (90) that interrupts power supply to the appliance upon the trigger (80) being activated. The GFI circuit (60) is electrically independent of electrical controller components of the appliance, thereby avoiding expensive software configuration and confirmation.

Abstract: An aircraft heated floor panel (10) comprising a weight-supporting level (20) and a heat-generating level (22) positioned below the weight-supporting level (20). The panel (10) can be characterized by the absence of a metal layer over its weight-supporting level (20).

Abstract: A patterned foil sheet heating element has a first discrete region patterned with a first plurality of holes forming multiple conductive ribbons and having a first sheet resistivity. It also has a second discrete region patterned with a second plurality of holes forming multiple conductive ribbons and having a second sheet resistivity. At least some of the multiple conductive ribbons in the first discrete region are in electrical continuity with at least some of the multiple conductive ribbons in the second discrete region, and the first discrete region and the second discrete region both adjoin a first junction strip of the foil heating element. An electrothermal heating assembly may be formed using such a patterned foil sheet sandwiched between two layers of material which may be thermally conductive and electrical insulative.