Abstract: Fiber optics and photovoltaic devices for optically controlling a conventional Electro-Hydraulic Valve (EHV) without need for external wiring. One laser, one fiber and one photocell located at the EHV are electrically passive, and inherently reliable. The system is much less susceptible to hard-over failure and unsymmetrical control because changes in any one of these elements will affect both directions equally.

Abstract: An airplane steering system which permits 180 degree turns with minimum tire scrub. The system involves steering of both the nose landing gear and the front and rear wheels of both main landing gear each consisting of three inline wheels; thus, the center of turn is placed between the main gears and allows the airplane to make 180 "pirouette" turns.

Abstract: The application of active noise control to influence the fan-noise components in engine ducts. The fan is used as a source of counter noise by introducing flow distortions upstream or downstream of the fan. Microphone arrays sense the noise and produce a control output signal for controlling a distortion producer. The control output signal for the distortion producer comes from a control algorithm utilizing the output of the microphone signals sampled at a defined rate based on the fan blade passing frequency.

Abstract: An aircraft modal suppression system which recognizes that the frequency and phase of the body bending mode varies when the weight of the aircraft differs from the design gross weight. An active damper notch filter which is tabulated as a function of aircraft gross weight is utilized, thereby enabling not only the frequency, but also the width and depth of the notch filter to vary according to the gross weight of the aircraft.

Abstract: A mist cooled distributed amplifier utilizing a connectorless module. The amplifier comprises modules that are connected to waveguides in a honeycomb. The RF signals are distributed to and combined from the modules using a distributed waveguide manifold. Cooling is accomplished by forming channels between the modules through which mist is transmitted and collected and condensed at the output end.

Abstract: A projector system having a process utilizing three-dimensional data, thereby allowing the system to account for rotational and translational differences between the projector and the object upon which the laser light is directed. Reference targets located on the object are in a known relationship to the projected three dimensional data. The reference targets are retro-reflective, such that light steered by the projector, when impinging on the reference targets, will return to the projector for detection and determination of the relative translation and orientation between projector and object. The three-dimensional data is then converted to a format suitable for projection using said translation and orientation information.

Abstract: A method of predicting the adhesion of a metal surface for painting or bonding comprising pressing an elastomer pad against the surface with a known force for a certain minimum time, measuring the force required to pull the pad away from the surface, and comparing that force with an empirically derived standard.

Abstract: Landing gear axle steering for an aircraft having a six wheel three axle truck. A set of wheels driven about a vertical shaft utilizes a single actuator alone without a walking beam.

Abstract: A semi-rigid, light weight insulation blanket is composed of a skeleton having porous cavities sandwiched between layers of fiber glass. The polyimide foam skeleton prevents sagging particularly in crown and upper sidewall areas of an aircraft thereby maintaining a predetermined offset from the skin fuselage reducing corrosion of the primary structure from moisture condensate. This configuration provides similar acoustic performance with reduced weight.

Abstract: A system for providing active noise control for turbulent airflow in a duct utilizing flow straightening upstream of bullet shaped microphones coupled to the noise control electronics thereby improving noise coherence between the input and error microphones and achieving noise reduction.

Abstract: A steerable landing gear for an aircraft having a six wheel, three axle truck has a steerable axle on either the rear or both forward and rear axles of the truck. A set of wheels driven about a vertical shaft utilizes a single actuator and a walking beam.The present invention relates to multi-wheel landing gear trucks or bogies for large aircraft and particularly to a method and apparatus for steering a set of wheels.

Abstract: A motor operated restrictor valve including a valve assembly for preventing noise at lavatories and galleys of an aircraft while permitting waste water to pass overboard through the drain mast.

Abstract: An ultrasonic 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, five (5) single probes, 188 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 stringer. Two (2) motors fore and two (2) motors aft of the immersion tank, produce information related to the position of the stringer with respect to the position of the transducer. The position encoder is spring-loaded against the stringer.

Abstract: A piercing grommet which pierces an insulation blanket. A snap-on retainer slides over a spiked portion of the piercing grommet and snaps in place adjacent the bottom of the spike. The spike can then be removed. A seal is created by contact adhesive between the insulation blanket and the grommet in order to prevent moisture ingress.

Abstract: A system for automatically controlling the braking of an aircraft to a desired setting upon landing or during a rejected takeoff. The inputs to the control system are airplane acceleration and airplane pitch. The output from the control system is an electric current which is sent to a hydraulic servo valve. This valve meters hydraulic pressure to the brakes.

Abstract: A steering method and system for large aircraft wherein during low speed taxi the main landing gear wheels are steered and the nose gear is free to castor. During high speed taxi such as during take off and landing, the main gear steering is locked out while the nose gear is steered.

Abstract: A projection system having a process utilizing three-dimensional data, thereby allowing the system to account for rotational and translational differences between the projector and the object upon which the laser light is directed. Reference sensors located on the object are in a known relationship to the three-dimensional data set to be projected, i.e., the reference sensors utilize the same coordinate system as the three-dimensional data set.

Abstract: A device for detecting hidden cracks in a structure includes a hand-held probe which is moved over the surface of the structure. The probe is connected to a computer terminal which also has connected thereto a monitor and a keyboard. Changes in the eddy currents in the underlying structure generates impedance changes in the coils of the probe. The resulting voltage values produce an image of the underlying structure and any cracks therein on the computer monitor. The system utilizes a number of procedures to compensate for liftoff problems, imbalance between coil channels, and differences in impedance reference values.

Abstract: An apparatus which can non-intrusively verify the integrity of shielding on electrical wiring. The method utilizes the natural resonance of the voltage transfer function of the shielded wire. The frequency of this resonance is an indication of the self inductance of the cable. A change in the resonant frequency indicates a change in the self inductance caused by a failure in the shield circuit.

Abstract: A cable clamp which utilizes a bayonet coupling attachment mechanism when coupled into an electrical connector. Attachment means of the cable clamp may utilize one of the two designs for two airplane general environments, such as the pressurized and unpressurized high vibration areas. Helical ramp grooves formed in the interior of a coupling ring act against bayonet pins mounted on a connector to effect coupling between the two components. A preloaded wavespring washer becomes effective during coupling of a Single Leg cable clamp used in the pressurized area, while a specially tapered spring washers become effective during the coupling procedure to maintain a no-motion condition on a Saddle-type cable clamp used in unpressurized, high vibration areas. Additionally, a plurality of detent pins are automatically shifted into a holding position at the completion of the coupling action, thereby further contributing to the maintenance of the coupled condition between the Saddle-type cable clamp and connector.