Abstract: A dual polarization antenna for use on an aircraft, preferably a helicopter or the like, permits practical and reliable high frequency radio communications in a severe non line of sight, nap of the earth flight environment. The antenna comprises both a horizontally polarized component and a vertically polarized component. The horizontally and vertically polarized components are formed of an integral element, which has a bend therein so that the two components have an angular orientation with respect to one another. The horizontally polarized component is oriented in a generally horizontal direction and the vertically polarized component is oriented in a generally vertical direction. Ideally, the horizontally and vertically polarized components are oriented as orthogonally to one another as possible, depending upon the airframe application.

Abstract: An apparatus for controlling the motion of a structural member on a space platform truss structure, launch vehicle, automobile, building, or the like is comprised of a first driving piezoelectric element and a second constraining piezoelectric element. The first piezoelectric element is embedded in or bonded onto the structural member. The second piezoelectric element is bonded onto the structural member, with a viscoelastic material (VEM) layer sandwiched between the structural member and the second piezoelectric element. The first and second piezoelectric elements are electrically connected in opposite phase. When the structural member is deformed by an applied force, the first driving piezoelectric element is correspondingly deformed, generating an electrical field. The electrical field is then applied in an opposite sense to the second piezoelectric element through the electrical connections, thereby oppositely deforming the second piezoelectric element with respect to the first piezoelectric element.

Abstract: A process for forming single piece metal alloy panel structures includes both superplastic forming and braze bonding steps, and is particularly adapted to superplastically formable materials which are not particularly diffusion bondable, such as aluminum alloys. The process involves constructing a worksheet assembly from a plurality of worksheets which are associated with a brazing alloy capable of brazing the worksheets. At least two of the worksheets are joined in facing contact with each other by welding in a preselected pattern. The perimeter of the joined worksheets is then sealed, with the provision of means for permitting the admission of pressurized gas therebetween, after which the worksheet assembly is placed in a forming die. The actual structure forming process begins by heating the die and its associated worksheet assembly to a temperature suitable for superplastic forming, and simultaneously applying gas pressure at the means for admission of pressurized gas.

Abstract: A closed loop fully self-contained actuation system for converting a mechanical input motion into a mechanical output motion, which actuates a device such as a flight control surface on an aircraft, comprises an input actuator including a first fluid pressurizing means responsive to the mechanical input motion, and an output actuator including a second fluid pressurizing means, as well as a flexible fluid line extending between the first and second fluid pressurizing means to provide fluid communication therebetween. The second fluid pressurizing means is responsive to fluid flow through the fluid line, thereby initialing the output motion. The system is advantageous because it requires no hydraulic pumps, no accumulators, no reservoirs, and no dynamic seals or mechanical joints, permitting great reliability. The actuation system may be easily folded in conjunction with the apparatus on which it is employed, for compact storage.

Abstract: A neutron detector for use in high energy flux environments. Multiple stacked arrays of biased Si PIN diodes are provided with adjustable lower and upper energy detection thresholds. Shielding along the sides and back of the detector limits the sensing to along the forward line of sight of the detector, and a short time gate limits sensing of an individual cell to a single event.

Abstract: There is provided by this invention a secure fiber optic communication system based on the Sagnac interferometer that allows multiple authorized users to communicate on the system by modulation and detection of two counterpropagating light beams. The security of the system is based on a combination of the information being modulated on the relative phase difference between the counterpropagating light beams and the low coherence length of the light source. In order for an intruder to intercept the signal, both counterpropagating beams must be accessed and the pathlength of the two beams matched to within a few coherence lengths of the light source so that an amplitude modulated output signal may be constructed. The system is further comprised of a random pathlength generator used to randomly vary the relative path length of the two counterpropagating beams. A light level alarm is provided that detects changes in the light level within the system.

Abstract: A hinge assembly capable of moving a panel or door between a flush, closed position and an outwardly opened position with at least 180 degrees of possible rotation of the panel. A housing is attached to the body at the edge of the door opening and locates a jack screw which drives a carriage in and out. On the carriage are located two idler shafts carrying fixed sprockets around which are wrapped a roller chain loop. The outer idler shaft is fixed to the panel and defines the hinge axis for the panel. One portion of the chain loop is fixed relative to the body such that, as the jack screw drives the hinge axis outwardly, the chain loop rotates the sprocket fixed to the outer idler shaft and the attached panel to an open position.

Abstract: A main rotor head is disclosed, which is adapted for mounting on a main rotor mast of a helicopter. A main rotor mast nut is threaded onto the main rotor mast in order to fasten the main rotor head to the mast. The key feature of the invention is a nut retention means, which comprises a cup-shaped round annular disk and closely surrounds the nut, preventing separation of the main rotor head from the main rotor mast should the nut fail during flight.

Abstract: A plate projecting in an aft direction from the blunt trailing edge of a wing. The plate extends across the span of the trailing edge, and may be either planar or curved in the spanwise direction. The plate is canted to form an acute depression angle with respect to a collinear extension of the chord line of each chordwise cross section of the wing. The depression angle may vary across the span of the trailing edge. The height location of the plate relative to the trailing edge thickness may also vary in a spanwise direction. The length of the plate may be anywhere from 0.5 to 2.0 times the thickness of the trailing edge.

Abstract: A simple and durable socket receptacle is adapted for receiving an electrical device such as a lamp which has a plurality of closely spaced contact pins. The receptacle comprises a dielectric means for receiving the contact pins which has a plurality of apertures which are in a one-to-one correspondence with the plurality of pins. When the device is inserted into the receptacle, each of the pins are received by a corresponding aperture. Above the dielectric pin receiving means is a space, into which extends at least one finger-like projection, upwardly from the pin receiving means. There is one projection for each two contact pins, and the projection is adapted to separate and insulate the plurality of contact pins from one another. A plurality of spring-like terminals also extend from the pin receiving means.

Abstract: A cargo ramp for an aircraft is constructed of two segments which are hinged together so that they may articulate about the ramp pitch axis. The first of the two segments is hinged to the cargo bed of the aircraft so that it may articulate relative to the cargo bed, again in pitch. The second segment abuts a surface to or from which cargo is to be transferred. The hinged ramp permits straight-across loading and unloading of cargo onto vehicles which have cargo bed heights different than the cargo bed height of the aircraft. In a modified embodiment, the ramp also compensates for a differential roll angle between the second ramp segment and the vehicle cargo bed. In this embodiment, the hinge connection between the two ramp segments permits relative motion of the second segment with respect to the first segment about its roll axis, as well as in pitch.

Abstract: A ramp system in a first embodiment incorporates a fore and an aft ramp section interconnected by a spindle which permits both pitch and roll movement of the aft section relative to the fore section. The fore section is hingedly connected to an aircraft structure at an opening thereof so that the fore section is capable of pitch movement relative to the aircraft. A set of hydraulic actuators provide controlled movement to the sections and additionally secure the sections in their desired positions. A set of rollers and curved tracks on adjoining portions of the sections both provide secure interconnection of the sections and prevent yaw movement of the aft section relative to the fore section. Rotation of the aft section relative to the fore section allows quick and simple disconnection and removal of the aft section and thereby provides interchangability with alternate aft sections adapted to provide the aircraft with alternate functional capabilities.

Abstract: A hollow core fan blade for a gas turbine engine, having a continuous leading edge, is fabricated using a four-sheet superplastic forming/diffusion bonding process which results in a cost-efficient and lightweight, yet strong, structure. The rotor blade is comprised of a face sheet which has a 180 degree bend therein so that the two face sheet ends are aligned. Bonded to opposing sides of the face sheet are first and second core sheets, between which is the hollow core. To fabricate the blade, a core sheet assembly is inserted inside the prepared face sheet, thereby forming a Ti-Pack (titanium pack) assembly having a plurality of pressure-tight cells. The Ti-Pack is inserted into a cavity within a die, after which the rotor blade, having predetermined design characteristics, is superplastically formed by heating the die and selectively pressurizing the plurality of cells.

Abstract: A fiber/metal laminate composite material is comprised of a plurality of metallic layers, reinforced with a plurality of fiber layers. The metallic layers are preferably aluminum, while the fibers in the fiber layers are preferably comprised of an aramid. The fibers are bi-directionally oriented. To provide the laminate with superior fiber failure resistance characteristics, the laminate is post-stretched along a post-stretch axis which bisects the two fiber axes.

Abstract: A tool for removing the dielectric insert of a metal shell electrical connector. The tool holds the shell and has a threaded press that pushes the dielectric insert out of the shell. The tool is then used to push a new dielectric insert into the shell. The tool is adjustable, such that it can be used on various sized connectors.

Abstract: There is provided by this invention a secure fiber optic communication system based on the Sagnac interferometer that allows multiple authorized users to communicate on the system by modulation and detection of two counterpropagating light beams. The security of the system is based on a combination of the information being modulated on the relative phase difference between the counterpropagating light beams and the low coherence length of the light source. In order for an intruder to intercept the signal, both counterpropagating beams must be accessed and the pathlength of the two beams matched to within a few coherence lengths of the light source so that an amplitude modulated output signal may be constructed. The system is further comprised of a random pathlength generator used to randomly vary the relative pathlength of the two counterpropagating beams. A light level alarm is provided that detects changes in the light level within the system.

Abstract: A compliant device attaching to the end of a robot arm and used in conjunction with a stereo vision system. The compliant device compensating for misalignment error in six degrees of freedom, that is x, y, z, pitch, yaw, and clocking (roll) between the end of the robot arm and a lock-on bushing when the compliant device is being inserted in a lock-on bushing. The compliant device having attached a stereo vision target providing positional feedback on the misalignment error between the lock-on bushing and the final position of the end of the robot arm to the stereo vision system.

Abstract: An on-board aircraft cargo handling system comprises a plurality of tines which are mounted within a cargo ramp and beneath its surface and are capable of extension aft of the ramp across a truck bed or the like. The tines have a plurality of rollers extending above their top surfaces for permitting easy movement of cargo across the tines. The ends of the tines are tapered to allow them to be pushed under the cargo to be moved. Pallet retainers, which consist of arm members which have finger-like projections on one end for allowing interengagement of the arm members with notches on the cargo, are mounted to the cargo ramp in such a way as to permit movement of the arms for aligning them with the cargo notches. Additionally, the cargo ramp surface includes pop-up chocks, which may be extended above the surface to lift the cargo, thus permitting forklift tines to be slid underneath.

Abstract: A fluid ejection nozzle is disclosed which facilitates a wide distribution of fluid therefrom and which permits the fluid flow rate to be easily adjustable. The nozzle is particularly adapted to a heat rejection system useful in a space environment. The nozzle includes a flow distributor positioned within an orifice of the nozzle housing which is comprised of a tongue member and an attached flow control block. Adjustment screws mounted through the nozzle housing permit axial movement of the flow distributor within the housing, thus controlling the flow rate of the fluid even to the extent of total shut-off. The tongue member is shaped to widely disperse the fluid, and includes turbulence generators such as roughening or ridges for facilitating its dispersion.

Abstract: A method for removing the dielectric insert of a metal shell electrical connector. The tool holds the shell and has a threaded press that pushes the dielectric insert out of the shell. The tool is then used to push a new dielectric insert into the shell. The tool is adjustable, such that it can be used on various sized connectors.