Abstract: A shield for the nozzle of the nozzle of a missile launched from beneath water, can be formed of a rigid plate spaced from the aft end of the nozzle to form a gap of area at least equal to the throat area of the nozzle. The gap reduces overpressure of the missile during launch while keeping water out of the nozzle by being directed perpendicular to the water flow direction.

Abstract: Apparatus for controlling the underwater course of a submarine-launched mile, by which gas contained within the missile body is vented from the interior of the missile, through ports in the missile exterior, into the water to alter the water pressure distribution over a portion of the exterior surface, thereby producing a desired pitching moment and resulting missile movement.

Abstract: A burst diaphragm sequence valve which effectively combines the structure a burst diaphragm with that of an ordinary swing check valve, the pivot of the ordinary swing check valve being replaced by an integral flexural hinge. The sequence valve provides a way to sequentially burn solid propellant hot gas generators which exit into a common gas manifold, thereby enabling gas-powered devices to operate for a longer time than the duration of one gas generator burn.

Abstract: An improvement to a variable-pressure solid-propellant-powered maneuvering ystem for spacecraft, enabling the system to operate for longer than one propellant burn time. At least two solid propellant gas generators are connected via a manifold to a plurality of nozzle valve clusters; at least one of the gas generators is connected to the manifold via a sequence valve which isolates that generator from the manifold until such time as it is desired to put that generator into operation.

Abstract: Stress from the ignition of a rocket is transferred from the rocket nozzle o the actuators and flexible joint seal which move the nozzle causing potential failure of the actuators. This stress can be relieved by using a snubber in the form of a flexible hollow conical toroidal bladder filled with incompressible fluid fitted snugly between the nozzle and the main body of the rocket. Such a snubber transfers the stress to the main body of the rocket through the snubber while deforming to allow the rocket nozzle to slew in response to control commands.

Abstract: A solid propellant to inhibitor bonding system for use in replaceable prolant grain assemblies is used with an inhibitor sleeve that has one end attached to an end closure having interior insulation, made of the same rubber insulation material as the inhibitor, and forming a cylindrical cavity for receiving a poured propellant mix. The bonding system is employed prior to pouring the propellant mix. This bonding system involves cleaning the interior surface of the cavity with freon solvent and brush applying a barrier coat, comprising an epoxy resin with amine curing agents, to the interior surface of the cleaned inhibitor. The barrier coat is then cured and a liner is then brush coated onto the cured interior surface of the barrier coat. The liner is then cured and the propellant is then cast into the cavity formed by the lined inhibitor sleeve and insulated closure.

Abstract: A coating slurry comprised of 42 percent silicon and 10 percent chromium metal powders; 45 percent lacquer base including toluene, xylene, and a polymeric binder; and 3 percent antisettling agent. After the slurry has been applied and then subjected to a high temperature vacuum processing, a ceramic coating is obtained which provides 3000.degree. F. high temperature oxidation protection for a refractory tantalum alloy substrate.

Abstract: A cost effective, efficient thermal insulation composition that will have ng shelf life and withstand severe high temperature and pressure conditions in high temperature solid propellant gas generators can be formed of an ethylene propylene, diene monomer (EPDM)/neoprene rubber binders containing silica powder filler and aramid fibers. The specific chemical constituents include EPDM elastomer, 2 Chlorobutadiene 1,3 elastomer, Silica hydrate, Polymerized Trimethyl Dihydroquinoline, Alkylated Diphenylamines and Diphenyl-p-Phenylendiamene, 40% a,a' Bis (Tert-Butylperoxy), Diisopropylbenzene, Napthenic Process Oil, Synthetic Polyterpene Resin, Aramid Fiber (0.25 inch), and Zinc Oxide, Technical.

Abstract: It is useful to be able to place a thermocouple in a plug in a spacecraft heat shield without disturbing the heat flow to the thermocouple. The thermocouple wire is ceramic coated before placement in the plug and a thin metal disc is placed in the bottom of the hole. The thermocouple wire is pressed into the disc to obtain good thermal contact.

Abstract: It is useful to a sonar instructor to have a device which simulates Doppler hifting of recorded sonar signals. Such a device can consist of a digitizer operating at a fixed rate storing data in RAM. A variable read rate is calculated based on the desired Doppler shifting. Data are read from RAM at a variable rate higher or lower than the fixed rate and converted D to A before being sent to the student sonar operator.

Abstract: A device of monitoring propellant burning within, and erosion of, a rocket motor case by measuring the voltage-induced capacity of gages on the external surface of the case is described. A burning propellant generates a conducting gas within the burn front inside the motor. The resultant voltage is caused by an injected voltage pulse on a metal igniter ring in contact with or capacitatively coupled to the gas.

Abstract: An apparatus for housing an explosive bridgewire, wherein the explosive bridgewire works in combination with both a multiple flyer disc containing a plurality of flyer elements and a tapered barrel element for directing the flyer elements toward an impact explosive.

Abstract: In order to increase the efficiency of solar cells, a monolithic stacked device is constructed comprising a plurality of solar sub-cells adjusted for different bands of radiation. The interconnection between these sub-cells has been a significant technical problem. The invention provides an interconnection which is an extremely thin layer of gold formed between the sub-cells by organometallic chemical vapor deposition. Such a layer tends to form beads which serve as a low resistance shorting interconnect while passing a large fraction of the radiation to the lower sub-cells.

Abstract: A free-electron laser has a wiggler for a linear electron beam comprising two sets of magnetic polepieces 26, 28 periodically spaced along opposite sides of the beam. The polepieces of one set 28 are displaced along the beam from the other set 26 by one-half period. A uniform longitudinal magnetomotive force generates fields between polepieces having transverse components 22 alternating between the sets 26, 28, providing a very short periodicity and hence, high frequency wave radiation.

Abstract: A gun for generating a multiple sheet beams 50 of electrons has a flat surfaced cathode 10 with parallel protruding ridges 12 of non-emitting material forming parallel focus electrodes for the sheet beamlets. A control grid of parallel bars 14 is aligned with the ridges 12 to reduce grid interruption. The beamlets may be focussed between support bars 54 of a foil anode 52 for passing the beam into a high-pressure volume such as a gas laser 48. The ridges are formed by inserting non-emissive bent sheets into grooves 58 in the cathode, which are dovetailed to hold them.

Abstract: Refractory metals or ceramics are diffusion bonded or densified by assembling the workpieces to be bonded, wrapping the assembly with carbon yarn, heating the wrapped assembly, cooling the assembly and unwrapping. The expansion of the workpieces together with the shrinking of the carbon yarn produces tremendous pressures which cause bonding and densifying of the workpiece.

Abstract: In a radiation therapy machine it is desirable to produce irregular radiation field shapes in order to shield critical organs not invaded by the tumor. A system is provided using a multileaf collimator formed of a multiplicity of heavy metal bar leaves driven relative to a pair of frames which are driven relative to jaws of a rectangular field collimator. A multiplicity of compensators, one attached to each leaf on one of the pair of frames is used to adjust the local intensity of the radiation within the field. The x-ray beam is limited to a fan with the jaws, the ends and selected parts of the fan are blocked by the multileaf collimator, and the intensity within various portions of the remaining beam is adjusted with compensators. The field of the fan beam is dynamically controlled by these means while the patient table is moved perpendicular to the plane of the fan beam.

Abstract: In a radiation therapy machine it is desirable to produce irregular radiation field shapes in order to shield critical organs not invaded by the tumor. A multileaf collimator is formed of a multiplicity of heavy metal bar leaves driven relative to frames which are driven relative to jaws of a rectangular field collimator by electric motors and flexible cables.

Abstract: An apparatus for planarizing an aluminum layer on a semiconductor wafer includes two deposition sources. The first source applies a refractory metal silicide layer to form a barrier to oxygen. The wafer is moved to a second deposition source which is an aluminum sputter device including a heater for the wafer, R.F. bias on the wafer and a magnetic mirror behind the wafer to move the plasma away from the wafer.

Abstract: A gyrotron interaction resonator 29 operating in a TE.sub.n1 cavity mode has an array of longitudinal slots 32 in the conductive wall 30. The slots 32 are spaced to couple to the unwanted TE.sub.n1 modes and to other modes of differing n and not to the desired mode. Wave-absorptive material 34 spaced from the inner cavity wall 28 and coupled to slots 32 absorbs the unwanted modes.