Abstract: A region of an airfoil to be protected from accreted ice is heated to reduce the strength of the bond between the ice and the airfoil, and is mechanically deformed to shed the accreted ice after the bond has been sufficiently weakened. Heating ceases before substantial water runback is generated. The mechanical deformation and the cessation of heating occur approximately simultaneously.

Abstract: An aircraft engine generates engine power by burning hydrocarbon fuel such as Jet-A. A minute quantity of the fuel is burned in such a manner as to generate no engine power, and the heat generated by the burning fuel is used to protect a region of a surface of a component of an aircraft. In one application, burner assemblies are located inside the splitter of a turbofan engine and the heat generated is used to deice or anti-ice the splitter and the inlet guide vanes of the engine. In another application, burner assemblies are located in an engine nacelle to deice or anti-ice the leading edge of the nacelle.

Abstract: An aircraft engine generates engine power by burning hydrocarbon fuel such as Jet-A. A minute quantity of the fuel is burned in such a manner as to generate no engine power, and the heat generated by the burning fuel is used to protect a region of a surface of a component of an aircraft. In one application, burner assemblies are located inside the splitter of a turbofan engine and the heat generated is used to deice or anti-ice the splitter and the inlet guide vanes of the engine. In another application, burner assemblies are located in an engine nacelle to deice or anti-ice the leading edge of the nacelle.

Abstract: A region of an airfoil to be protected from accreted ice is heated to reduce the strength of the bond between the ice and the airfoil, and is mechanically deformed to shed the accreted ice after the bond has been sufficiently weakened. Heating ceases before substantial water runback is generated. The mechanical deformation and the cessation of heating occur approximately simultaneously.

Abstract: A region of an airfoil to be protected from accreted ice is heated to reduce the strength of the bond between the ice and the airfoil, and is mechanically deformed to shed the accreted ice after the bond has been sufficiently weakened. Heating ceases before substantial water runback is generated. The mechanical deformation and the cessation of heating occur approximately simultaneously.

Abstract: A region of an airfoil to be protected from accreted ice is heated to reduce the strength of the bond between the ice and the airfoil, and is mechanically deformed to shed the accreted ice after the bond has been sufficiently weakened. Heating ceases before substantial water runback is generated. The mechanical deformation and the cessation of heating occur approximately simultaneously.

Abstract: A region of an airfoil to be protected from accreted ice is heated to reduce the strength of the bond between the ice and the airfoil, and is mechanically deformed to shed the accreted ice after the bond has been sufficiently weakened. Heating ceases before substantial water runback is generated. The mechanical deformation and the cessation of heating occur approximately simultaneously.

Abstract: An electro-thermal or hot gas anti-icer of the “running-wet” type is mounted at the leading edge of an airfoil. Mechanical de-icers are mounted on the surfaces aft of the anti-icer. The mechanical de-icers throw off ice without creating runback water, thereby eliminating runback refreeze ridges caused by a known hybrid ice-protection system. Advantageously, the de-icers are of a type in which the airfoil has a semi-rigid skin that forms an aerodynamic surface of the airfoil, and in which there is at least one mechanical actuator for flexing the skin.

Abstract: A serpentine etched foil heater has a segmented serpentine conductor group made up of a plurality of spaced-apart elongated serpentine conductive strips that are connected in parallel and are everywhere aligned with each other. Advantageously, central conductive strips are wider than are conductive strips along the edges. Further advantageously, the conductive strips are bridged by conductive regions that extend along lines of constant voltage. This makes it possible to handle the heater element without causing it to become tangled. The heater is especially suitable for low voltage applications.

Abstract: An electro-thermal or hot gas anti-icer of the "running-wet" type is mounted at the leading edge of an airfoil. Mechanical de-icers are mounted on the surfaces aft of the anti-icer. The mechanical de-icers throw off ice without creating runback water, thereby eliminating runback refreeze ridges caused by a known hybrid ice-protection system. Advantageously, the de-icers are of a type in which the airfoil has a semi-rigid skin that forms an aerodynamic surface of the airfoil, and in which there is at least one mechanical actuator for flexing the skin.

Abstract: The present invention is de-icing system that uses electromagnetic actuators mounted within the airfoil of an aircraft to effect de-icing. Advantageously, the actuators have low voltage and current requirements. Each actuator includes conductive strips fabricated on a flexible dielectric sheet. The conductive strips are wound into coils with the actuator shaped into a flattened elongated tube. The axis of the winding coils is coincident with the longitudinal axis of the elongated tube.

Abstract: An electrical heating element is provided in the coupler body of a coupler of the type used for railroad applications. The heating element heats the coupler to evaporate moisture and to prevent ice from forming. This lengthens the service life of the pin assemblies and reduces the frequency with which the coupler requires servicing.

Abstract: Two parts are adhesively bonded together in such a manner that after the parts have been separated, any remaining adhesive can be easily removed. This is done by placing a flexible cable-containing layer of adhesive between the two parts. The cable is arranged in a serpentine pattern and has a free end which is outside the layer.

Abstract: A fault detection circuit for a plurality of DC loads uses a reference load as a benchmark. The voltages at the centerpoints of the loads to be monitored are monitored and compared with the voltage of the centerpoint of the reference load. The comparison is affected by faults which do not affect all loads equally (as by a short or open) and is unaffected by faults which do affect all loads equally (as by changes in voltage of the source).

Abstract: A control system and circuit has a positive feedback characteristic but is nonetheless stable. Stability is achieved by superimposing a negative feedback loop with a short time constant and a positive feedback loop with a long time constant. The system and circuit are useful in situations where the sensor and the controlled variable (e.g. a heater) are well-coupled.

Abstract: A fault detection circuit for a plurality of three-phase loads uses a wye-connected reference load as a benchmark. The voltages at the centerpoints of the loads to be monitored are monitored and the largest monitored voltage is identified. This largest voltage is compared with the voltage of the centerpoint of the reference load. The comparison is affected by faults which do not affect all loads equally (as by a short or open in one of the phases of one of the loads) and is unaffected by faults which do affect all loads equally (as by changes in voltage of one of the phases of the source).

Abstract: Wire is flat braided into a straight component on a braiding machine, and carrier threads keep the component from deforming as it is drawn off the machine. The carrier threads are removed. The braid component is cut into straight strips with terminals connected to the ends of the strips. The braid component with leads extending therefrom is mounted to or in the surface of a high strain aerodynamic component. The axis of the heater is parallel to the direction of applied stress. The wires lie along directions of reduced strain.

Abstract: A plurality of electrically conductive wires is connected between two terminals and cross over each other at crossover points. Wire segments connect adjacent crossover points. All such adjacent connected crossover points have different potentials when a voltage is connected between the terminals. This forms a screen which protects an engine from damage caused by foreign objects carried into the engine intake. When a power source is connected to the terminals, the screen is heated to prevent the accretion of ice.

Abstract: A pass network includes a switching element having a non-smooth conduction characteristic in the transition region about zero-crossover of an AC signal to be switched. A bypass network is connected in parallel with the pass network and has a smooth conduction characteristic in that transition region.