Abstract: A method and apparatus for detection of rare earth metal oxide inclusions in non-magnetic metal. The method utilizes a D.C. magnetic search field coupled with a magnetic field sensor for detecting the response of a rare earth metal oxide casting fragment inclusion through the bending and amplification of the ambient magnetic field at the defect location.

Abstract: Lightning protection utilizing lightweight electrically conductive coatings with a conductance of approximately 220 to 350 mhos per square co-cured or secondarily bonded to the outer surface of thin skin composite structure. Selection of either 2 to 3 ounces per square yard or aluminum mesh of 1 to 1.5 ounces per square yard, depending on corrosion compatibility, satisfy the conductance requirement and has shown superior lightning protection over heavier weight conductive coatings.

Abstract: A measuring instrument and method for measuring paint and coating thickness on poorly conductive graphite substrates. The instrument uses a microwave amplifier, a measurement cavity, and an optional reference cavity with supporting electronics to measure the apparent changes in the length of the measurement cavity due to the changes in the paint and coating thickness. The measurement cavity resonates when the measurement cavity is set upon the test surface. The oscillating signal is sent through a) directly to a microwave frequency counter, or b) a reference cavity tuned to give the desired slope detection response to cover the paint and coating thickness range allowed. The filtered response of the reference cavity is converted to a dc level signal proportional to paint thickness. It is presumed that the expert user will have access to a PC allowing instant conversion—via a stepped calibration plate—to paint thickness in mils from electrical data.

Abstract: CMOS circuits are made resistant to erroneous signals produced by the impact of high energy charged particles (commonly known in the literature as Single Event Upset or SEU) by the addition of upset immune transistor structures into the circuits in such a way that they block and dissipate the erroneous signal. The added transistor structures are made immune to SEU by placing them in well diffusions that are separate from the rest of the circuit and biasing those wells such that the electric fields surrounding the transistors are very low in comparison to the rest of the circuit. Signal blocking is achieved with an SEU immune transistor that is in an “off” state whenever other circuit transistors that deliver signals through it are potentially sensitive to SEU. Dissipation is achieved with either a resistor or low current drive transistor that spreads the SEU signal out over time thereby reducing its voltage change to an acceptable level.

Abstract: A method of removing and reinstalling multiple floor-beams concurrently while minimizing aircraft movement. The airplane is supported with jacks in a manner that minimizes internal shear and bending moment stresses. All floor-beams needing to be replaced are removed concurrently. All floor-attach structure such as floor panels, intercostals, seat-tracks, hard points, cargo handling equipment, and electrical and hydraulic standoffs is also removed. Deformation of the airplane is monitored and any significant deformation is restored. A floor-beam complex consisting of floor-beams, and all floor-attach structure such as floor panels, intercostals, seat tracks, hard points, cargo-handling equipment, and electrical and hydraulic standoffs is installed in place of the removed floor structure. The floor-beam complex has splices to facilitate handling during installation. More than one floor-beam complex may be required for a complete airplane.

Abstract: An ultrasonic one pass inspection system for determining the presence, location, and size of flaws in laminated structure such as an “I” stiffener in a single inspection cycle. The exemplary system includes an immersion tank, six (6) single probes, 184 transducers, four (4) motor assemblies, two (2) encoder assemblies, a collection tank, and a recirculation assembly. The probes are designed to match the shape of the stiffener. Two (2) motors fore and two (2) motors aft of the immersion tank, produce information related to the position of the stiffener with respect to the position of the transducer. The position encoder is spring-loaded against the stiffener.

Abstract: A differential positive feed mechanism that is coupled in-line or axially with a drill, reamer or cutter for use in limited access areas and feeds the tool into a workpiece when driven by an external rotary power source.

Abstract: A connector assembly mounted on a printed wiring board allowing modifications to be made to the connectivity using simple wiring techniques. The connector assembly contains special contacts providing three connections. One end of the contact mates with the source or destination of the signals in a modular electronic device. The other end accepts a wired contact for making additional connections not contained in the printed wiring board. The middle section of the contact makes a compliant connection to the printed wiring board. A signal can be disconnected from the printed wiring board by removing the contact and replacing it with a contact that is insulated from the printed wiring board.

Abstract: A loop resistance tester (LRT) for shield integrity testing comprising three elements: a “drive” current coupler, a “sense” current coupler, joint probes, and an instrument assembly. A low-power excitation current is sent from the instrument into the drive coupler, which is essentially a transformer. This induces a current in the electrical cable under test, as long as that cable and the connected structure form a continuous current path, or loop. This induced loop current is detected by the “sense” current coupler (transformer) and is measured by the instrument. The ratio of the loop voltage to loop current, as phasor values, gives the complex loop impedance, the real part of which is the loop resistance.

Abstract: A method for producing stable atmospheric pressure glow discharge plasmas using RF excitation and the use of said plasmas for modifying the surface layer of materials. The plasma generated by this process and its surface modification capability depend on the type of gases used and their chemical reactivity. These plasmas can be used for a variety of applications, including etching of organic material from the surface layer of inorganic substrates, as an environmentally benign alternative to industrial cleaning operations which currently employ solvents and degreasers, as a method of stripping paint from surfaces, for the surface modification of composites prior to adhesive bonding operations, for use as a localized etcher of electronic boards and assemblies and in microelectronic fabrication, and for the sterilization of tools used in medical applications.

Abstract: A method for producing stable atmospheric pressure glow discharge plasmas using RF excitation and the use of said plasmas for modifying the surface layer of materials. The plasma generated by this process and its surface modification capability depend on the type of gases used and their chemical reactivity. These plasmas can be used for a variety of applications, including etching of organic material from the surface layer of inorganic substrates, as an environmentally benign alternative to industrial cleaning operations which currently employ solvents and degreasers, as a method of stripping paint from surfaces, for the surface modification of composites prior to adhesive bonding operations, for use as a localized etcher of electronic boards and assemblies and in microelectronic fabrication, and for the sterilization of tools used in medical applications.

Abstract: A class of planar arrays having broad frequency range applications for source location, source imaging or target illumination with projected beams is described in this disclosure. The non-redundant arrays are circularly symmetric and made up of a plurality of sensing and/or transmitting elements arranged so as to substantially eliminate grating lobes for a broad range of frequencies. Signals received from or transmitted to the elements are appropriately phased to control the beam of the array.

Abstract: A measuring instrument and method for measuring paint and coating thickness on conductive and poorly conductive substrates. The instrument uses a microwave amplifier, a measurement cavity, and a reference cavity with supporting electronics to measure the apparent changes in the length of the measurement cavity due to the changes in the paint and coating thickness. The measurement cavity resonates when the measurement cavity is set upon the test surface. The oscillating signal is sent through a reference cavity tuned to give the desired filtered response to cover the paint and coating thickness range allowed. The filtered response of the reference cavity is converted to a dc level signal that serves as input to a data acquisition circuit. The data acquisition circuit converts the input signal to digital form so that the calibration method may be used to associate a given response with the corresponding paint and coating thickness.

Abstract: Very large aircraft landing gear using single mounted eight wheel bogie on dual shock struts. A primary or main two-stage shock absorber and a semi-articulating secondary or auxiliary single-stage shock absorber, each of which are mounted using the second and third axles as pivot joints in a four axle, eight wheel truck beam.

Abstract: A method for optical signaling for electrical switch control, and in addition, optical powering of the electrohydraulic servovalve by means of opto-electric conversion using solar cells with a battery backup and dual redundancy for reliability. Optical power sources are e.g., laser diode, LED, or high intensity lamp.

Abstract: An ultrasonic one pass inspection system for determining the presence, location, and size of flaws in laminated structure such as an “I” stiffener in a single inspection cycle. The exemplary system includes an immersion tank, six (6) single probes, 184 transducers, four (4) motor assemblies, two (2) encoder assemblies, a collection tank, and a recirculation assembly. The probes are designed to match the shape of the stiffener. Two (2) motors fore and two (2) motors aft of the immersion tank, produce information related to the position of the stiffener with respect to the position of the transducer. The position encoder is spring-loaded against the stiffener.

Abstract: An all electric remote control system for a pressurized load carrying non-plug cargo door whose electric lock system is isolated from the remainder of the control system to preclude common mode electrical failures from attempting to unlock and unlatch the door.

Abstract: An aircraft landing gear brake arrangement wherein a landing gear stub axle and brake pressure plate are integrated. Each of the integrated assemblies is attached to a support fitting which pivots on the truck axle thereby causing the torque links to be unaffected by steering operations.

Abstract: A grounding contact member for electrically connecting cooperating metal shells in a coupling comprises a metal band divided along both edges into several spring contact fingers that are bent inwardly into two U-shape portions. The contact member is located in an annular recess around the inside of a coupling ring with the fingers at one end engaging the metal shell on which the coupling ring is mounted and the fingers at the other end engaging the other metal shell to which the coupling ring is connected.

Abstract: An ultrasonic one pass inspection system for determining the presence, location, and size of flaws in laminated structure such as an "I" stiffener in a single inspection cycle. The exemplary system includes an immersion tank, six (6) single probes, 184 transducers, four (4) motor assemblies, two (2) encoder assemblies, a collection tank, and a recirculation assembly. The probes are designed to match the shape of the stiffener. Two (2) motors fore and two (2) motors aft of the immersion tank, produce information related to the position of the stiffener with respect to the position of the transducer. The position encoder is spring-loaded against the stiffener.