Abstract: Properties of thin films are monitored in real time by measuring the interactions of the light from an injection laser diode with the thin film adjacent to one of the facets of the laser diode by an associated photodetector. Thickness, index of refraction and other properties can be measured as a function of the output power, slope efficiency and threshold current of the laser diode.

Abstract: In a NOTAR.TM. (No tail rotor) system for a helicopter, the addition of vortex generators in the longitudinal slots or nozzles which produce the circulation control portion of the system which combines with a jet thruster and fluid resource to replace the tail rotor.

Abstract: A particularly useful circuit board support device is disclosed which provides a rigid protected environment for a circuit board during curing, transport, testing and assembly. The circuit board support devices are modular and may be stackably rigidly joined into convenient multiple units.

Abstract: The present invention is directed to an improved, multi purpose measuring device for determining various parameters of an externally threaded member. In particular, the invention includes a substantially ring shaped housing slidably supporting at least one pair of gage plugs having measuring assemblies mounted thereon. As the gage plugs are selectively moved through the housing to bring the measuring assemblies into contact with an externally threaded member for determining various parameters such as the actual and functional pitch diameters, the minor diameter and the concentricity of the threaded member.

Abstract: Disclosed is an advantageous device and method of simultaneously testing multiple wheel transducers, typically on modern aircraft, with the ability of performing the test remotely, as from the cockpit.

Abstract: Nozzle contained within tubular housing. An annular manifold concentrically surrounds and abuts the outside of the housing. The manifold communicates with an external source of water. A cylindrical transducer is located within the housing. A hollow cone having an exit opening formed by a truncated vertex and an open base forms the front of the nozzle. The face of the transducer which emits ultrasonic waves is situated adjacent to the base of the cone. An annular passageway concentrically surrounds the transducer. The passageway runs axially towards the front of the nozzle before turning radially inward towards the nozzle's centerline. The axial section of the passageway communicates with the manifold through radial ports. The section of the passageway that turns inward communicates with the base of the cone, and also directs flow of water so that its confluence is on the emitting face of the transducer. The water subsequently flows out the exit opening in a steady state column.

Abstract: A parachute ring release mechanism with a spring incorporated to insure disengagement of the parachute risers. The ring release is structured such that the parachute risers may be released by either one of two rip cords.

Abstract: A microstrap patch antenna with a substantially omni-directional radiation pattern includes an upper hemisphere microstrip patch radiator working against a ground plane and a lower hemisphere microstrip patch radiator working against a ground plane, the ground planes being oriented in close proximity and spaced apart from each other. One of the radiators is excited in left hand circular polarization and the other in right hand circular polarization such that their fields add constructively across their ground planes to achieve an omni-directional radiation pattern.

Abstract: A multi position optical switch requiring no electrical service at the actuator and capable of continuous or discrete sensing of switch position is disclosed.

Abstract: The process for forming a metallic sandwich structure having a curved surface, particularly a surface curving about more than one axis, such as a quadric surface partially by direct displacement and partially by a fluid interface. Additionally, means to restrain the work sheets being formed with respect to the shaping fixture which allow a portion of the work sheets to flow into the forming cavity before absolute restraint is applied and the restraining means function independently of the clamping force of the press.

Abstract: A true mass fuel gaging system for aircraft utilizing multiplexing of tank unit measurements in or adjacent a fuel tank for improved accuracy and fault isolation. The system provides dual equipment channels for redundancy throughout all data processing portions of the system and also uses extensive built-in testing (BIT) routines so that upon detection of a fault an alternative channel can be switched into use. Detected fault locations are displayed in the cockpit with the fuel quantity displays. The system also provides displays of center of gravity measurements derived from fuel mass and location.

Abstract: There is provided an optically pumped laser having highly reflective coatings on opposite sides such that multiple reflections of radiation between the reflective coatings of the opposed sides produce lasing in a transverse mode. A plurality of diode lasers mounted in a linear array along the opposed sides with reflective coatings provide pumping emission to the laser. An optical alignment means consisting of prisms receive the stimulating emission from individual diode lasers and align individual stimulating emission such that it is colinear with the reflective radiation within the laser cavity.

Abstract: A device and method facilitates grounding shielding, including hardware and structures necessary to allow proper connection, practice the steps of the method, minimize pigtail length, facilitate the formation of a wire bundle assembly, facilitate repair and installation, and result in materials and labor savings.

Abstract: A polarized grounding pin incorporating a spring, to provide continuous electrical conductivity between mated connector shells.

Abstract: There is provided by this invention an optical heterodyning device comprised of a semiconductor heterostructure having a forward biased electrode connected thereto for optically mixing an input signal frequency with a local oscillating frequency in the separate confined laser cavity and a reverse biase electrode connected thereto for detecting the intermediate frequency produced. The local oscillator provides preamplification in the laser cavity and can be effectively phase locked to the input signal frequency.

Abstract: A system based on the usage of a Sagnac interferometer operating in a dual sensing mode is described which allows the determination of the location and amplitude of a time varying disturbance on a single fiber.

Abstract: A plurality of inlet and outlet channels for receiving and exhausting respectively the flow of a heat exchange medium directed to the inlet channels are located adjacent a plate provided with generally parallel, elongated orifices extending in the direction of and in registration with the inlet and outlet channels. A heat exchange panel is disposed adjacent the plate on the side thereof opposite that of the channels such that the medium entering the input channels travels through the orifices of the plate to the heat exchange panel and then from the panel to and through the outlet channels.

Abstract: A plenum in combination with a heat exchange panel and a panel structure having a large number of closely spaced orifices of equal size. The plenum area relative to that of the orifice area is such that a pressure head in the plenum is maintained to provide a constant flow of heat exchange medium from the plenum through the orifices to the heat exchange panel.

Abstract: The invention feeds balls to a connected ball propelling machine, such as those used to propel softballs and baseballs. The feeder includes a chute angled with respect to gravity so that balls loaded into an upper end thereof tend to travel through the chute but are restricted in their movement by an abutment surface. The abutment surface is formed on a bumper member extending upwardly into the chute. A rotating shaft extends across the chute in proximity to and behind the abutment surface. The shaft includes a pair of hooks extending about the bumper member so that upon rotation of the shaft, the hooks lift one ball at a time over the bumper member. This allows the lifted ball to continue its travel down the chute and into the ball propelling machine. A cam included on the shaft, and switches are used to control a motor connected to rotate shaft.

Abstract: Disclosed is an apparatus and method for locating the position of a normal shock in a fluid flowing in a duct.