Abstract: The disclosure concerns a means for cooling the leading edges and trailing dges of turbine blades by cross-stream injection. Cooling is achieved by ejecting coolant from holes opposite either the leading or trailing edges of the blades, or both, with coolant distributed by the jet mixture on the leading edge and by recirculation in the dead air region on the trailing edge.

Abstract: A dual-position nozzle having a stationary outer support structure or thr holder and an inner sustain throat assembly which translates during boost-sustain transition is provided. The throat holder includes inner and outer metal support rings joined by three tubular struts. During boost operation, the sustain nozzle assembly is mechanically joined to the throat holder by a split beveled retaining ring which is engaged in a groove in the inner metal ring of the throat holder. Upon command, expanding gases act to withdraw a pin from a gap in the retaining ring permitting the sustain nozzle to translate under viscous and pressure forces to the sustain phase position.

Abstract: Ferroelectric crystals and ceramics prepared with tailored domain patterns hich are selected to enhance or suppress certain modes of vibration which may include those normally unattainable such as, for example, second harmonics.

Abstract: An easily maintainable interface for magnet dewars which includes a low h leakage disconnect fitting that retains the vacuum integrity of both the dewar and the transfer line is provided. The fitting includes a bayonet-type insert having separate coils disposed about a central conduit for cooling or heating the unit depending upon intended use. Liquid helium is introduced axially through the bayonet which is adjustable to a purge position wherein either gaseous or liquid helium may be introduced to clean, heat or cool the unit, or a flow position wherein liquid helium is passed through the bayonet into the supply line.

Abstract: The disclosure concerns an electrical contact for conducting high current densities in a minimum of space and with improved connection between the contact and the socket. The contact includes a split, internally tapered circular sleeve which is mounted in spring-loaded engagement in a socket. A tapered contact pin conforms to the split sleeve and when inserted causes the sleeve to be wedged between the pin and the socket. The compression spring generates large contact pressures in a relatively short length of connector travel, thus enabling the mechanical advantage of the coupling mechanism to accomplish connector engagement with minimal operator effort.

Abstract: A radiation suppressor for exhaust turbine or other engines which signifitly reduces the lock-on range of infrared seeking missiles is provided. Engine exhaust gases are the sole power source for driving an exhaust turbine which includes a self-contained turbo-fan assembly and a surrounding plenum-shroud assembly both of which are structurally supported by the aircraft or other vehicle-cooling air duct assembly. The turbo-fan assembly comprises a turbine wheel having a top or outer fan for providing both hot metal and plume cooling air and a central centrifugal blower to partially cool the hollow turbine blades. The duct assembly is combined with ambient air passages to distribute plume cooling air, while a plenum-shroud assembly which surrounds these assemblies includes internally cooled radial vanes disposed in a turbine shroud as well as an outer fairing having flow passages for cooling air.

Abstract: A method and apparatus for determining the value of a Doppler frequency shift component .DELTA.f present in a signal f .+-. .DELTA.f employing a correlation process which utilizes the Mellin transform and is scale invariant. The location of the correlation peak in the reference coordinate system used provides a measure of the magnitude of .DELTA.f. The sequence of steps involved in the correlation process when optical apparatus is used include forming a transmittance pattern of the signal f .+-. .DELTA.f, which has a horizontal scale that is the natural log of the time scale of the original signal, forming a similarly scaled transmittance pattern of the reference signal, f, and utilizing the first patttern in the input plane of a frequency plane correlator that has a holographic matched spatial filter that is produced from the second pattern and contains a term corresponding to the conjugate of the Mellin transform of the reference signal in its frequency plane.

Abstract: A device for rapidly decelerating a high velocity projectile in a liquid ium, e.g. water, while preventing both excessive high inertial loading of sensitive projectile components and high impact loading of the device itself is provided. A plurality of deployment panels are released at a selected depth and initially opened by leaf springs and thereafter by water flow. Acceleration of the panels is controlled by a piston actuated by the panels which displaces water in a chamber in the drogue body through a suitable orifice.

Abstract: An oleo strut oil level indicator is provided which includes a rod slidably xtending through a landing gear or other metering pin contacting the strut floating piston at one end and terminating at a frangible disc at the opposite end. Excessive oil loss in the strut produces a commensurate displacement of the floating piston toward the frangible disc, causing the opposite rod end to rupture the disc at a selected piston position and exposing a colored low oil level indicator to view thereby visually indicating a condition of potential danger.

Abstract: An acousto-optic image scanner employing pulses of acoustic surface waves which propagate along the length of a piezoelectric crystal performing as a traveling phase grating to diffract a collimated monochromatic light beam which has a spatial light distribution corresponding to the information content of a line of the image. The light beam propagates through the width of the crystal thus providing an extensive electro-optic interaction length for increased diffraction efficiency. The light intensity at a first-order spot is detected to provide a temporal signal representative of the light distribution of an image line. Scanning of colored images can be accomplished by utilizing a chromatic beam and detecting the light at the first-order spots corresponding to the three different wavelengths present in the illuminating beam.

Abstract: A gas/liquid separator for separating entrained gases such as air from lid such as oil in hydraulic systems under extreme flight conditions is provided. High density liquid substantially devoid of gas bubbles is forced toward the perimeter of a liquid chamber through centrifugal force by imparting rotational velocity to incoming liquid, causing low density air-entrained liquid and large gas bubbles to collect in the center of the chamber. The high density liquid is discharged from an upper slot in the chamber while liquid with entrained gas bubbles is urged centrally upward into a second chamber where further separation occurs. Gas-free liquid from the upper chamber is collected and discharged centrally within opposed outlets communicating with the slot to provide a pumping action which augments liquid flow into and out of the upper chamber. Gas is bled from the upper chamber.

Abstract: Systems which utilize an optical signal to carry information and employ a ree-wave heterodyne detector of the type having a cubic response do not require a local optical signal source in the receiving apparatus since the optical signal as generated provides two optical signal components for the detector's operation. The third signal is supplied by a local microwave oscillator. A high resolution optical wave ranging system having an improved field-of-view is disclosed which uses such a composite signal in conjunction with a pair of three-wave heterodyne detectors.

Abstract: A method and electro-optical apparatus for correlating two functions, f.sub.1 (x,y) and f.sub.2 (x,y) which are shifted, scaled and rotated versions of each other without loss of signal-to-noise and signal-to-clutter ratios as compared to the autocorrelation case. The coordinates of two correlation peaks provide an indication of the scale and orientation differences between the two functions. In performing the method, the magnitudes of the Fourier transforms of the functions are obtained, .vertline.F.sub.1 (.omega..sub.x, .omega..sub.y).vertline. and .vertline.F.sub.2 (.omega..sub.x,.omega..sub.y).vertline. and then a polar coordinate conversion is performed, and the resultant functions F.sub.1 (r,.theta.) and F.sub.2 (r,.theta.) are logarithmically scaled in the r coordinate. The functions thus produced F.sub.1 (e.sup..rho.,.theta.) and F.sub.2 (e.sup..rho.,.theta.) are Fourier transformed to produce the Mellin transforms M.sub.1 (.omega..sub..rho., .omega..sub..theta.) and M.sub.2 (.omega..sub..rho.,.omega.

Abstract: A non-metallic, high strength, high temperature resistant external or internal strengthening for fiber optics cables is provided. The strengthening may be in various forms such as internally deployed filaments, outer woven mesh fibers, segmented cylinders, helical wrap ribbon, etc., and is made from single high-strength crystal fibers preferably of sapphire, i.e. .alpha.-Al.sub.2 O.sub.3. The non-conductive strengthening crystals have a low density, are highly crush resistant and meet severe environmental fiber optic sensor and data transmission requirements.

Abstract: A transport system for fragile instruments such as the motion sensors used n aircraft flight controls which are very susceptible to damage during handling, shipment and installation is provided. Individual sensors are mounted on a plate that is suspended inside the permanent housing of the equipment by springs which act as shock-vibration insulators. The housing is spring-isolated in an outer casing for transport, and the plate is permanently secured to the housing at the installation site simply by tightening bolts which extend through the housing.

Abstract: Correlation methods and apparatus are disclosed which make use of Mellin transforms that are scale and shift invariant. There is no loss in the signal-to-noise ratio of the correlation, and data is available for determining any scale difference between the input and reference data.

Abstract: A real-time radar processor utilizing a coherent optical system for provig target fine range and Doppler/azimuth angle data with increased signal-to-noise and signal-to-clutter ratios. Radar signals detected by a linear phased array or successive echo signals detected by the receiver are arranged in a 2-D input format for parallel processing in a multi-channel 1-D optical correlator. Target range and azimuth angle reference data may be stored in a matched spatial filter hologram or recorded in a 2-D format similar to that of the detected radar signals according to which of three different correlation configurations are employed in the optical system. The coordinates of the correlation peak in the output plane of the correlator are proportional to the target's fine range and Doppler/azimuth angle, depending upon the type of radar signals being processed.

Abstract: A cooling arrangement for a gas turbine exhaust nozzle is provided which ludes a plurality of heat shield panels slidably positioned on tracks mounted on the nozzle casing. The panels are spaced apart to permit thermal expansion and include impingement baffles which are attached thereto intermediate the panels and the casing. Holes in the impingement baffles direct cooling air against the interior surface of the panels. The cooling air is directed by suitable means such as slots or film holes to form a film of cooling air along the surface of the panels exposed to hot gases.

Abstract: A regulated power supply which may be of the A.C.-to-D.C. type utilizes a ries arrangement of inverters because of a voltage rating of these inverters with respect to the magnitude of the D.C. driving voltage available either as a consequence of rectifying an A.C. voltage source or other reasons. The regulator has a self-balancing feature which insures that all of the inverters equally share the D.C. driving voltage and also includes a protection feature which safeguards the inverters against damage caused by a malfunction of any one of the units.

Abstract: The critical velocity at which magnetic bubbles can propagate within a matic material is increased by establishing an easy axis of magnetization within the material. This axis is either growth-induced or strain-induced. In one embodiment, the material has a curvature imparted to it which places it under a uniaxial strain and this induces the magnetic easy axis.