Abstract: A propellant injector for a liquid rocket engine has an injection cylinder and moving piston in the cylinder. The cylinder on one side of the piston opens into the combustion chamber of the engine. The other side of the piston has a coaxial tubular portion projecting therefrom. A pair of valve members have concentric sleeves slidably mounted respectively on the inside and outside surfaces of the tubular portion of the piston. The outer ends of the concentric sleeves and tubular portion extend through an end wall of the injection cylinder. The valves open and close passages extending through the piston by relative axial movement of the sleeves and the piston. Pneumatic actuator means, connected to the outer ends of the sleeves and tubular portion, moves the sleeves axially relative to the piston to open the valves and move the piston toward the end wall of the injection cylinder to force propellant through the passages into the combustion chamber.

Abstract: A laser of the type in which laser gas molecules are pumped by an electron beam has a gas-cooled window forming the interface between the electron beam source and the laser gas. The window includes a metallic foil mounted on a supporting frame with a parallel thin layer of material transparent to the electron beam positioned between the foil and the electron beam source. Helium or other cooling fluid is circulated in the space between the foil and the intermediate layer for conducting heat away from the foil. The helium may be at an intermediate pressure less than the pressure of the laser gas on one side of the foil but greater than the vacuum of the electron beam source to reduce foil stresses.

Abstract: A novel gimbal mechanism utilizes one or more support arms so rotatably coupled to support structure and to an article whose position is to be controlled as to permit such article to be reoriented along any axis within a cone defined by axes of rotation of the gimbal's support arms.

Abstract: A diesel engine having a fuel vaporizing chamber in which liquid fuel is vaporized prior to injection into the precombustion chamber.

Abstract: A mechanism is described for deploying a shield from a space vehicle or the like. Such a shield may be employed for minimizing radar echo, for protecting the vehicle from solar radiation, or for providing a bumper for minimizing damage from micrometeoroids. A spring loaded mechanism is provided so that the shield can be folded into a compact package for launch of the space vehicle. The spring loaded mechanism further provides for rapid development of the shield when restraints are released. Arrangements are provided for deploying semi-cylindrical shields and quarter spherical shields.

Abstract: A retractable nozzle assembly for a rocket has an extendable nozzle section which is concentric with the main nozzle and is movable telescopically from a retracted position to an extended position. A drive assembly moves the nozzle section into the extended position in which it forms an extension of the main nozzle. Cam members, movable by the same drive assembly after the nozzle is moved to its extended position, wedge detent members radially into a detent groove, providing a positive lock between the two nozzle sections.

Abstract: A high reflectivity mirror produces a substantially 90.degree. phase shift between p and s plane polarization components of the reflected light by applying a plurality of super-imposed transparent layers on the reflective surface of a substrate. Adjacent layers are made of materials of substantially different indices of refraction. The thickness of substantially all of the layers is less than a quarter wavelength at the center frequency of the incident light and the thickness of the layers differ from each other in a predetermined manner to control and produce exactly 90.degree. phase shift between the s and p polarization components while providing maximum reflectivity over a wide frequency band.

Abstract: There is described apparatus for combining a plurality of pulsed laser beams into a single beam by a rotating mirror assembly. A rotor supports a plurality of individual mirrors arranged in a plurality of axially spaced planes, one plane for each beam. The mirrors in successive planes are angularly and radially spaced relative to mirrors in the other planes. Incident beams are pulsed successively in synchronism with rotation of the mirrors. Each beam in succession is reflected by a mirror in successive planes along a common axis to form a single reflected beam.

Abstract: A singlet delta oxygen generator 10 comprises a static or motionless mixer 12 having a gas inlet 14 through which chlorine gas reactant is introduced into the static mixer and a liquid inlet 16 through which the basic sodium hydroxide/hydrogen peroxide solution is introduced. As the reactants pass through static mixer 12, the gaseous products and liquid by-products are formed. The product stream passes through liquid/gas separator 26 wherein the liquid by-product stream is diverted to sump 28 and the gaseous product stream is conveyed to a low volume trap 30. The temperature of trap 30 is maintained at approximately -80.degree. C. so as to solidify and thereby remove any water or hydrogen peroxide vapor which might remain in the product stream. From the low volume trap 30, the product stream is then conveyed to chlorine trap 34 wherein any excess chlorine gas present in the system is retained.

Abstract: A multistage, vaneless centrifugal pump having an input stage, an output stage, and a plurality of intermediate stages with each of said intermediate stages comprising a divider plate serving to separate successive stages, and a center plate having a recess formed in the rear surface of said center plate serving as a vaneless radial diffuser and having a recess formed in the front surface of said center plate serving to receive fluid from a preceding stage and to guide said fluid in a helically converging path to be delivered to the input of an impeller.

Abstract: A plurality of arcuate, secondary (fuel) nozzle members are juxtaposed, so that respective two of them define between them a curved, primary slit nozzle, producing a primary (oxidizer) expansion flow while the two flows mix downstream, predominantly transversely to the expansion. The nozzle members are mounted in the aperture of a plate; large-scale assemblies are described.

Abstract: A slide guide 22 for a tube-type heat exchanger has a tubular geometry and comprises saddle 28 and slots 26 interposed one each between fingers 24. Saddle 28 positions slide guide 22 within tube support sheet port 30 while fingers 24 are biased so as to conform to the ovality of tube 12 and dissipate dynamic loads across a relatively large tube surface area.

Abstract: This invention relates to liquid hydrocarbon motor fuels improved by the addition of an azido compound. Specifically, the azido compounds of the present invention have the following general formulas N.sub.3 --R.sub.2, N.sub.3 --R.sub.2 --N.sub.3, N.sub.3 --R.sub.3 --O--R.sub.4 --N.sub.3, N.sub.3 --R.sub.3 --CO.sub.2 --R.sub.4 --N.sub.3, ##STR1## wherein R is an alkyl, alkyl hydroxy, primary alkyl ether, and alkyl ester and mixtures thereof; R.sub.2 is an alkyl or alkyl hydroxy, R.sub.3 and R.sub.4 are the same or different and comprise lower alkyl radicals and mixtures thereof; x is an integer from 1 to 5' y is an integer from 3 to about 20; and z is an integer from 3 to 20.

Abstract: An improved diesel engine wherein fuel is preheated and vaporized within the precombustion chamber during a substantial portion of the engine cycle in which the precombustion chamber is isolated from the cylinder by an isolation valve. Compressed air from the engine cylinder is admitted to the precombustion chamber near the end of the compression stroke by the timed opening of the isolation valve. The precombustion chamber is shaped to enhance mixing of the compressed air with the preheated and vaporized fuel.

Abstract: A multi-actuator deformable mirror and control system which comprises a copper-surfaced, aluminum faceplate supported by a flexure strut attached to an aluminum-backed structure and actuated by nineteen differential ball screw mirror actuator assemblies. The actuators are driven directly by direct current stepping motors capable of 400 steps/rev when operating in "half step" mode. A 10.mu. meter per revolution differential pitch in the screw provides a resolution of 1.mu. inch per motor step. An alternating current dither actuator comprising a plurality of piezo-ceramic elements is connected one each in series with said actuator assemblies for providing both tagging and real time dynamic corrections.

Abstract: A precombustor 10 for use in diesel engines comprises a precombustion chamber 12, a fuel spray nozzle port 18 through which a fuel spray nozzle 20 may be incorporated into the precombustion chamber 12, an igniter port 22 for an ignition means adjacent to said spray nozzle port 18, and a supersonic DeLaval nozzle 14 integrally incorporated into the precombustion chamber 12 opposite said spray nozzle port 18 for enhancing the injection of air into the precombustion chamber 12. Axially connected to the throat area of the DeLaval nozzle 14 is a two-dimensional subsonic diffuser 34 and flow passage 30 for transferring air from the diesel piston to the precombustion chamber 12 and combustion gases from the precombustion chamber 12 into the diesel cylinder.