Abstract: A method for protecting an aircraft component from ice formation uses a thermally conductive film. The film includes a polymer, an electrically conductive material, and a sufficient concentration of hexagonal boron nitride to provide adequate heat transfer properties, and have high thermal conductivity, peel strength, and shear strength. The films can include thermoset polymers, thermoplastic polymers, or blends thereof, and can also include reinforcing materials such as fiberglass, carbon fiber, metal mesh, and the like, and thermally conductive fillers, such as aluminum oxide, aluminum nitride, and the like. The films can be included in composite materials. The films can be used as part of a layered structure, and used in virtually any application, for example, various locations in aircraft, where heating is desirable, including nacelle skins, airplane wings, heated floor panels, and the like.

Abstract: An ice protection system (30) wherein a heater array (50) comprises a series of consecutive electrothermal heaters (51) which proceed one after another in a substantially aft-fore-aft path. A power source (60) supplies the heater array (50) with electrical energy and a heater interface (80) switches each heater (51) into either an ON condition or an OFF condition. The heater array (50) can be architected to effectively and efficiently protect an ice-susceptible aircraft surface (40) by strategic heater shaping, concentrated power-density allocation, and/or tactical heating-episode execution.

Abstract: An engine nacelle inlet lip includes both acoustic treatment and electric heating for ice protection. The inlet lip has a composite outer skin and a composite inner skin, with the composite outer skin having at least one integrated heater element embedded in the composite material. An acoustic cellular core positioned between the outer and inner skin acts to attenuate fan noise from the engine. Covering the outer skin and overlying the acoustic core is a perforated erosion shield having a first set of openings that pass entirely thorough its thickness. The composite outer skin includes a second set of openings such that sound waves can pass from an inner barrel portion of the inlet lip through the erosion shield, outer skin, and heater element to the underlying acoustic cellular core.

Abstract: The invention includes a composite ice protection heater for an aircraft. The composite heater includes at least one electrically insulating layer, and at least one electric heater element comprising an electrically conductive layer bonded to the insulating layer. The conductive layer may include a pre-impregnated woven fabric that includes a plurality of threads that include an electrically conductive material, such as carbon or graphite fibers. The composite heater can be incorporated into a composite surface structure of an aircraft. The conductive layer and insulating layer may include a plurality of spaced openings through the layers that cooperate with an underlying open-cell matrix to attenuate noise at the associated surface of an aircraft. A desired electrical resistance of the conductive layer may be obtained by introducing a plurality of discontinuities in the layer, such as spaced holes or slits.

Abstract: An electro-thermal ice protection system for an airfoil comprises: a metal foil heater including an integral parting strip, the metal foil heater configurable to cover at least a portion of a leading edge of the airfoil with the integral parting strip disposed along an air-stagnation zone of the leading edge; and a controller coupled electrically to the metal foil heater for controlling electrical energy from a power source to the metal foil of the heater in accordance with a pulse duty-cycle and for controlling power to the parting strip of the heater to maintain the air-stagnation zone virtually free of ice formation.