Abstract: An aircraft control position indicator is provided that displays the degree of deflection of the primary flight control surfaces and the manner in which the aircraft will respond. The display includes a vertical elevator dot/bar graph meter display for indicating whether the aircraft will pitch up or down, a horizontal aileron dot/bar graph meter display for indicating whether the aircraft will roll to the left or the right, and a horizontal rudder dot/bar graph meter display for indicating whether the aircraft will turn left or right. The vertical and horizontal display or displays intersect to form an up-down-left-right type display. Internal electronic display driver means receive signals from transducers measuring the control surface deflections and determine the position of the meter indicators one each dot/bar graph meter display.

Abstract: The invention is an apparatus which allows selective testing of aircraft or other vehicular components without requiring disassembly of the vehicle or components. The invention consists of a broad-band noise source 11, a guide 12 to direct the acoustic energy, soft sealing insulation 17 to seal the guide to the noise source and to the vehicle component, and noise measurement microphones 13, 14, both outside the vehicle at the acoustic guide output and inside the vehicle to receive attenuated sound. By directing acoustic energy only to selected components of a vehicle via the acoustic guide, it is possible to test a specific component, such as a door or window, without picking up extraneous noise which may be transmitted to the vehicle interior through other components or structure. This effect is achieved because no acoustic energy strikes the vehicle exterior except at the selected component.

Abstract: A telemetry system in which a plurality of transmitters are frequency shift keying modulated. A receiver including an overlapping detector retains the transmitted data when there is no overlap in data transmitted and discards the transmitted data when there is an overlap in data transmitted.

Abstract: This invention is an aircraft 10 with a system for increasing the lift-drag ratio over a broad range of operating conditions. The system positions the engines and nacelles 15 over the wing 12 in such a position that gains in propeller 16 efficiency is achieved simultaneously with increases in wing lift and a reduction in wing drag. Adverse structural and torsional effects on the wings 12 are avoided by fuselage mounted pylons which attach to the upper portion of the fuselage 11 aft of the wings. Similarly, pylon-wing interference is eliminated by moving the pylons to the fuselage. Further gains are achieved by locating the pylon surface area aft of the aircraft center-of-gravity, thereby augmenting both directional and longitudinal stability. This augmentation has the further effect of reducing the size, weight and drag of empennage components 13.

Abstract: Method and apparatus unaffected by vibrational environments for obtaining measurements using Raman Doppler Velocimetry. Two laser beams, a pump beam 18 and a probe beam 22, are focused by a lens 21 to a point 25 in a flow 11. A lens 26 collimates the two beams. A beam splitter 27 dumps beam 18 and beam 22 is reflected by a corner cube 28 back to lens 26. Lens 26 then focuses the beam back to point 25. The reflected beam 22 and the backward and forward scattering at point 25 are detected by a detector 30 and processed by a boxcar averager 31. The lens 26 and corner cube 28 combination, called a retrometer 29, ensure that the measurements are unaffected by vibrations.

Abstract: A double reference pulse phase locked loop for measuring the phase shift between tone burst signals initially derived from the same periodic signal source (voltage controlled oscillator 16) and delayed by different amounts because of two different paths. A first path is from transducer 12 to surface 14 of sample 11 and back, and a second path is from transducer 12 to surface 15 and back. A first pulse phase locked loop including phase detector 26 and phase shifter 22 forces the tone burst signals delayed by the second path in phase quadrature with the periodic signal source. A second pulse phase locked loop including phase detector 21 forces the tone burst signals delayed by the first path into phase quadrature with the phase shifted periodic signal source.

Abstract: Sulfone-ester polymers containing pendent ethynyl groups and a direct and multi-step process for preparing same are disclosed. The multi-step process involves the conversion of a pendent bromo group to the ethynyl group while the direct route involves reacting hydroxy-terminated sulfone oligomer or polymers with a stoichiometric amount of 5-(4-ethynylphenoxy)isophthaloyl chloride. The 5-(4-ethynylphenoxy)isophthaloyl chloride and process for preparing same are also disclosed.

Abstract: This invention is for a passive laminar flow airfoil which has an upper skin 12 and lower skin 14 joined at a trailing edge 16. A leading edge structure 20, such as de-icing equipment, is joined to the upper and lower skins by interface mechanisms 30 and 35. Generally, the interface mechanisms are forward facing steps, with or without adjacent gaps, shaped and dimensioned to accomplish laminar flow using standard airfoil manufacturing techniques.

Abstract: This is a device for suspending a store 66 from an aerodynamic support surface, such as an aircraft wing 12, and more specifically for improving upon single pivot decoupler pylons by reducing both frequency of active store alignment and alignment system space and power requirements. In the described embodiment, two links 36 and 42 suspend a lower pylon/rack section 60, and releasably attached store 66, from an upper pylon section 16 mounted under wing 12. Links 36 and 42 allow lower pylon section 66 to rotate in pitch about a remote pivot point 68. A leaf spring 30 connected between lower section 60 and electrical alignment system servomechanism 18 provides pitch alignment of the lower section 60/store 66 combination. Servomechanism 18 utilizes an electric servomotor 20 to drive gear train 21 and reversibly move leaf spring 30, thereby maintaining the pitch attitude of store 66 within acceptable limits. Damper 54 strokes when lower section 60 rotates to damp large oscillations of store 66.

Abstract: The disclosure relates to a deployable M-braced truss structure that is efficiently packaged into a compact stowed position and expandable to an operative position at the use site. The M-braced configuration effectively separates tension-compression and shear in the structure and permits efficient structural design. Both diagonals and longerons telescope from an M-braced base unit. They are deployed either pneumatically, mechanically by springs or cables, or by powered reciprocating mechanisms. Upon full deployment, the diagonals and longerons lock into place with a simple latch mechanism.

Abstract: A skin friction force measuring device having a first pivoted 13 L-shaped arm 12, a second arm 16 pivoted 17 on one end of the L-shaped arm with a sensing element 20 attached to an end of the second arm. In response to skin friction forces on the sensing element 20 the arms are pivoted about the two pivots and two nulling means 23, 28 force the pivots back to their zero positions. The outputs of the two nulling means are indicative of the skin friction forces along two perpendicular axes, x and y, in the plane of the sensing element.

Abstract: A method and apparatus for controlling power to a precipitator 27. After each spark the power to the precipitator is reduced to zero, increased along a fast ramp 15 for a fixed period of time and then increased along a slow ramp 17 until a spark occurs. The fast and slow ramp data is computed and stored (memory 48) and then retrieved after each spark. The data retrieved is the data corresponding to the firing angle at the last spark. Means are provided (selector 51 and memory 52) for dividing (frequency divider 45) the retrieved slow ramp data by a number to select the number of sparks per minute. Also the AC current and the AC voltage in the power to the precipitator are detected and the RMS values are obtained (32 and 34) and compared 35 and if the difference is above a predetermined value the power is disconnected (relay 36 and contacts 23 and 24).

Abstract: An aromatic condensation polyimide film that is approximately 90% transparent at 500 nm, useful for thermal protective coatings and the like, and the processes for preparing same by thermal and chemical conversion are disclosed. An essential feature of the invention for achieving maximum optical transparency films requires utilizing recrystallized and/or sublimated specific aromatic diamines and dianhydride monomers and introducing phenoxy or thiophenyl separator groups and isomeric m,m'- or o,p'-oriented diamines into the polymer molecular structure. The incorporation of these groups in the polymer structure serves to separate the chromaphoric centers and reduce the formation of inter-chain and intra-chain charge transfer complexes which normally cause absorptions in the UV-visible range.

Abstract: A nebulization reflux concentrator 10 for removing trace gas contaminants from a sample gas is disclosed. Sample gas from a gas supply 40 is drawn by a suction source 42 into a vessel 11. The gas enters vessel 11 through an atomizing nozzle 16, thereby atomizing and entraining a scrubbing liquid solvent drawn through siphon tube 22 from a scrubbing liquid reservoir 21. The gas and entrained liquid rise through concentrator 10 and impinge upon a solvent-phobic filter 28, whereby purified gas exits through filter 28 and contaminated liquid coalesces on filter 28 and falls into reservoir 21.

Abstract: A solar pumped laser has its lasing path lengthened by forming a square loop in the lasing path by means of bending mirrors. Solar radiation is collected and concentrated into a donut shaped intensity pattern. This intensity pattern is directed onto the lasing path such that there is a maximum fit of the solar intensity pattern to the square loop laser cavity.

Abstract: Sulfone-ester polymers containing pendent ethynyl groups and a direct and multi-step process for preparing same are disclosed. The multi-step process involves the conversion of a pendent bromo group to the ethynyl group while the direct route involves reacting hydroxy-terminated sulfone oligomer or polymers with a stoichiometric amount of 5-(4-ethynylphenoxy)isophthaloyl chloride. The 5-(4-ethynylphenoxy)isophthaloyl chloride and process for preparing same are also disclosed.

Abstract: A column longeron latch assembly 72 provides the securing mechanism for the deployable, telescoping column 12 of a hoop/column antenna 10. Column 12 is an open lattice structure with three longerons disposed 120.degree. apart as the principle load bearing member and is deployed from a pair of eleven nested bays 22, 23 (FIG. 2) disposed on opposite sides of a center section 21 under the influence of a motor-cable-pulley system (FIGS. 3 and 4). Longeron latch 72 is a four bar linkage mechanism using the over-center principle for automatically locking the longeron sections into position during deployment and serves to unlock the sections when antenna 10 is to be re-stowed. A spring pack 61 disposed in an end of each longeron serves to absorb stress forces on the deployed column through the cam head piston and abutting latch from an adjacent longeron.

Abstract: A display for aiding the pilot of an aircraft in anomalous wind environments. Wind velocity components are measured by an instrument 11, processed by a computer 12 and a vector generator 17 and then displayed as a vector 34 on the display shown in FIG. 3. A signal F indicative of flap position selects a flight validated lift curve which is displayed as a lift curve channel 42. During normal wind conditions the cursor 35 marking the termination of vector 34 is in the channel of curve 42. However, during wind anomalies cursor 35 moves outside the channel. It then becomes the task of the pilot to control the aircraft such that cursor 35 will move back into the channel.

Abstract: A collapsible-expandable truss structure 16 including first and second spaced surface truss layers (18, 20) having an attached core layer 22 is disclosed. The surface truss layers are composed of a plurality of linear struts 40 arranged in multiple triangular configurations with each linear strut being hinged at its center 41 and hingedly connected at each end thereof to a nodular joint 25. A passive spring 64 serves as the expansion force to move the folded struts from a stowed collapsed position to a deployed operative final truss configuration. Damper 62 controls the rate of spring 64 expansion for synchronized deployment of truss 16 as the folded configuration is released for deployment by restraint belts 72a and 73a synchronously extending under the control of motor (71) driven spools 72 and 73.

Abstract: A joint for joining composite material such as segments of the skin 12 and 13 of an aircraft. Tapered splice plates 30 and 31 overlap the ends 14 and 15 of the skin. The thickest portion 34 of the splice plates overlap the ends 14 and 15. The splice plates are clamped together on the skin segments 12 and 13 by fasteners 50, 52, 54 and 56. The tapered splice plates are designed to minimize load transfer at the outermost bolt row 56 coincident with maximum bypass stress in the skin segments while simultaneously maximizing load transfer in both the skin segments and splice plates at the innermost bolt row 50.