Abstract: An amplifier circuit is placed in the wheel assembly of the landing gear of an aircraft. The amplifier circuit amplifies a signal whose frequency is proportional to the speed of the wheel prior to transmitting the signal over a transmission line to sensing and control circuits. This permits a high frequency signal to be generated at the wheel assembly and insures that the signal has sufficient power to be sensed by a remotely located sensing circuit even though the signal may be attenuated by the capacitance in the transmission line. This permits a higher frequency signal to be generated than previously possible. This provides greater wheel speed resolution and enhanced sensitivity for aircraft landing gear anti-skid systems.

Abstract: A method and apparatus for testing the integrity of the dielectric coating on an elongated member. The apparatus includes a pair of opposing, conducting surfaces that can be biased against the dielectric surface, a source of high voltge that can be switchably imposed on the conducting surfaces, a ground for completing an electrical circuit between the elongated member and the source of high voltage, and an electrical circuit for detecting the passage of current through the electrical ground. A first visible indicator on the apparatus shows when the high voltage is applied to the conducting surfaces and a second visible indicator shows when a current is detected through the electrical ground. This apparatus allows the conducting surfaces to be moved longitudinally along the elongated member to test the dielectric integrity of virtually the entire dielectric surface in a single pass.

Abstract: A tubing inside an aircraft fuel tank is encircled by a dielectric support and wear sleeve that is comprised of two members that are clamped together circumferentially around the tubing. The members include projecting portions having an adhesive applied thereto along mating surfaces to rigidly couple the support sleeve members to each other. The mating surface is a circumferential arc that provides complete overlap of a portion of the two support sleeve members. The adhesive extends circumferentially along the mating surface to provide sufficient dielectric strength due to the extended length of the adhesive coupling. The tubing and sleeve are supported by a support assembly including a clamp, bracket and tank wall. The sleeve material has the necessary thickness and length to provide dielectric isolation of the tube from the support assembly. The sleeve is designed having tight tolerances along the outside diameter to permit axial motion with respect to the clamp while restraining radial motion.

Abstract: A plurality of metal conduits for fuel for hydraulic fluids extend through an aircraft fuel tank made of non-metallic materials such as carbon-epoxy. The conduits are attached to wall portions of the tank at spaced apart locations. The conduits are spaced apart from each other and are each spaced away from such wall portion of the tank. A dielectric insulator such as teflon or polyimide is provided on each conduit.

Abstract: A brake control system particularly suited for use on aircraft having hydraulically applied carbon disc brakes.Braking is controlled by displacing a foot pedal. A first transducer, connected to the pedal, measures the magnitude of displacement and produces a first electrical signal. A second transducer, connected to wheel means, measures the speed of the wheel means during braking and produces a second electrical signal. The first and second electrical signals are transmitted to control circuit means which compares them. If the second signal indicates that wheel means deceleration is not substantially proportional to foot pedal displacement, the control circuit means sends a control signal to electrically operate a pressure control valve which meters hydraulic fluid pressure to operate the brakes such that wheel means deceleration is substantially directly proportional to foot pedal displacement.