Abstract: A programmable electronic time delay initiator includes a digital time-delay circuit that counts in response to a dual-resonator clock and, at the end of the programmed time delay, gates the pre-stored charge on a capacitor to a semiconductor bridge initiator to fire an explosive. The timer circuit includes a combined crystal/RC oscillator that provides high accuracy oscillations from the crystal or oscillations from the RC components in the event the crystal fails. The timer circuit functions in response to multi-part serial commands delivered on a conventional two-wire path. The timer is initially powered-on to provide power to a capacitor that supplies power to the time-delay and related circuits. An initial ATTENTION pulse initializes the circuitry and starts a watchdog timer that counts a fixed number of clock cycles and resets the logic if a following WRITE, ARM, or FIRE command is not received.

Abstract: A process forms decoy flare pellets which satisfy predetermined burn requirements without milling additional grooves into the pellet flare material after that material is consolidated. The process includes providing sufficient surface area to the flare material during consolidation to eliminate the need for milling. Consolidated flare pellets are then coated with an ignition composition and installed in a decoy flare housing.

Abstract: A computer-implemented system and method for evaluating gas bag inflator designs are disclosed, including an inflator state machine having slots for signals corresponding to predetermined gas dynamic and heat transfer characteristics of a gas bag inflator at a specified time. Inflator state machines having one or more chambers, and zero or more deflectors, screen packs, burst disks, and vents are supported. Initial temperatures, pressures, and chamber gas contents may be specified, as may the geometry and other characteristics of gas generant pills. A controller in the state machine accesses a chemical database to obtain information about enthalpy, viscosity, and other properties of gas generant combustion products, igniter combustion products, and other compounds present within the gas bag inflator.

Abstract: A process of preparing 5-aminotetrazole ("5-AT") which proceeds at substantially neutral pH is disclosed. In the process, cyanamide or dicyandiamide and an azide salt are reacted at elevated temperature in the presence of an acid reagent. The acid reagent has a pK.sub.a in the range from about 3 to about 7. Large quantities of hydrazoic acid are not produced during the reaction. Upon completion of the reaction, the reaction mixture is acidified to a pH less than 3 to protonate the 5-AT. Several variations of the acidification step permit control of particle size and morphology. The precipitated particles are isolated to yield 5-AT.

Abstract: A nonsolvent process of synthesizing bis(2,2-dinitropropyl)formal (BDNPF) is disclosed. In the process, 2,2-dinitropropanol (DNPOH) is reacted at low temperature with a formaldehyde source in the presence of a protic acid catalyst, such as H.sub.2 SO.sub.4, HCl, H.sub.3 PO.sub.4, or HBr. To inhibit byproduct formation, the reaction temperature is maintained from about -30.degree. C. to 30.degree. C. Upon completion of the reaction, the reaction solution is quenched with water and washed with an aqueous hydroxide ion solution. The hydroxide ion concentration should be sufficient to neutralize the protic acid catalyst during the quenching step and to solubilize unreacted 2,2-dinitropropanol as well as other aqueous soluble byproducts in the reaction solution. The BDNPF product is extracted with a low boiling temperature polar organic solvent, such as methyl tert-butyl ether (MTBE) or equivalent solvent. The organic solvent is evaporated to yield usable BDNPF product.

Abstract: A system and method for inflating and deflating an air bag within a vehicle without substantially exposing the occupants of the vehicle to toxic compounds, particulates, and other contaminants in the gas mixture used to inflate the air bag. The system includes a flow guide having an exterior port in fluid communication with the ambient air outside the vehicle, an air bag port connectable in fluid communication with the air bag, and an internal bore permitting fluid flow between the exterior port and the air bag. A nozzle disposed within the flow guide bore is secured to an inflator containing a pressurized gas source. The nozzle and flow guide preferably have certain geometric characteristics disclosed herein. In operation, gas is expelled from the gas bag inflator through the nozzle at a velocity sufficient to entrain ambient air from outside the vehicle. The entrained ambient air mixes with the gas expelled through the nozzle, and the mixture inflates the air bag.

Abstract: A sodium-azide-free gas-generating composition includes an oxidizable inorganic fuel, such as a metal, and an oxidizing agent containing oxygen and a metal. The fuel and the oxidizing agent are selected such that water vapor is produced upon reaction between the inorganic fuel and the oxidizing agent. Although a number of inorganic fuels can be employed, a suitable fuel can be a transition metal, another element such as silicon, boron, aluminum, magnesium, an intermetallic compound, hydrides of these metals and mixtures thereof. The oxidizing agent comprises a metal hydroxide, a metal hydrous oxide, a metal oxide hydrate, a metal oxide hydroxide, or mixtures thereof. The fuel and oxidizing agent are selected such that essentially no gases other than water vapor are produced.

Abstract: A pyrotechnically driven device for restricting the area of the nozzle throat in a solid propellant rocket motor is disclosed. In one embodiment, the device includes a piston support mounted to the rocket motor in the exit cone. A restrictor is attached to a piston which is supported by the piston support. The restrictor is movable from a retracted position outside the nozzle throat to a restricting position within the throat upon actuation of the device. The piston and attached restrictor are driven by a pyrotechnic driving means that is actuatable separately from the solid propellant of the rocket motor. A locking means locks the restrictor in its restricting position.

Abstract: An electrically actuated igniter squib is formed by welding a cup containing a pyrotechnic material to a header inserted in the cup, thus forming a hermetic seal. The diameter of the header exceeds the diameter of the cup and the two are joined by forcing, under pressure, the header into the cup to achieve a tight readily welded joint.

Abstract: A sodium-azide-free gas-generating composition includes an oxidizable inorganic fuel, such as a metal, and an oxidizing agent containing oxygen and a metal. The fuel and the oxidizing agent are selected such that water vapor is produced upon reaction between the inorganic fuel and the oxidizing agent. Although a number of inorganic fuels can be employed, a suitable fuel can be a transition metal, another element such as silicon, boron, aluminum, magnesium, an intermetallic compound, hydrides of these metals and mixtures thereof. Suitable oxidizing agents are selected from basic metal carbonates and basic metal nitrates. The fuel and oxidizing agent are selected such that substantially nontoxic gases are produced such as mixtures of water vapor and either carbon dioxide or nitrogen.

Abstract: A rugged quick-response thermocouple for use in measuring the temperature of a gas flow includes two wires formed of different metals and electrically joined at an exposed junction. A ceramic sheath substantially surrounds the two wires except near the junction. The sheath is surrounded by a stainless steel tube. The junction is positioned adjacent an end of the ceramic sheath. In one embodiment the wires are coated with an insulator and the insulator is positioned against the flat end of the sheath. The exposed junction resists damage from gas flows and from corrosive compounds in the gas mixture.

Abstract: A process for preparing salts of 5-nitrobarbituric acid involves allowing an in situ generated a compound represented by formula (I): ##STR1## wherein R.sub.1 and R.sub.2 are the same or different and are, H, C.sub.1 to C.sub.8 alkyl or substituted C.sub.1 to C.sub.8 alkyl, aryl or substituted aryl, to condense with urea to obtain a condensation product; and neutralizing the condensation product with at least one organic base and another cation source (MX) at a pH.gtoreq.7 and recovering the thus formed salt of 5-nitrobarbituric acid.

Abstract: A cutting assembly for cutting propellant from a rocket motor. The cutting assembly includes a plurality of first cutting wheels, second cutting wheels and secondary cutters which are mounted to a mounting head. The mounting head is attached to an arm for rotation about an axis of rotation. Means are provided for rotating the mounting head. The cutting wheels are mounted to the mounting head for rotation about an axis of rotation transverse to the axis of rotation of the mounting head. Each cutting wheel includes a plurality of cutting blades extending outwardly from the rim. The cutting blades are each configured with a radially extending cutting edge for cutting in a direction substantially normal to the axis of rotation of the mounting head.

Abstract: Polyether organic compounds are described which have both imine and hydroxyl functionality. These materials are synthesized by reacting a primary amine with an aldehyde or ketone to form a Schiff base. By definition, a Schiff base comprises the reaction product of a primary amine and an aldehyde. In this case, however, unlike conventional Schiff bases, the reaction product possesses both hydroxyl and Schiff base functionality. In one embodiment of the invention, such a product is produced by the reaction of a polyoxyalkyleneamine (Jeffamine) with p-nitrobenzaldehyde and glycidol. The result is a polyether having both hydroxyl and Schiff base functionality. The compounds produced in this manner are particularly useful as bonding agents in the formulation of solid propellants. The bonding agents provide superior performance, while avoiding the problems encountered when using existing bonding agents.

Abstract: An insensitive high explosive is obtained by using a dicyandiamide (DCDA), ammonium nitrate (AN), guanidine nitrate (GN), ethylene diamine dinitrate (EDDN) eutectic melt binder in combination with ammonium perchlorate (AP) oxidizer, fine RDX (1 .mu.m to 10 .mu.m particle size), and aluminum metal as a fuel. The fine RDX particles improve performance, boosterability, and sensitivity. The inclusion of AP greatly improves air blast by adding oxygen to the reaction and insuring complete combustion of the ingredients. The aluminum extends the pressure pulse. The ratio of materials is formulated to obtain the lowest known processing temperature.

Abstract: A system and process for obtaining near real time, non-destructive inspection and characterization of surfaces. The system includes an infrared light source which is directed on a surface to be inspected. A portion of the reflected light is gathered and directed through an optical filter arrangement which separates the light into a plurality of sets of wavelengths which correspond to particular physical properties of the thin film, such as absorbance. The intensity of each set of wavelengths is detected by optical detectors and the resulting signals analyzed to characterize the surface.

Abstract: A sodium-azide-free gas-generating composition includes an oxidizable borohydride fuel and an oxidizing agent containing oxygen and a metal. The fuel and the oxidizing agent are selected such that water vapor is produced upon reaction between the borohydride fuel and the oxidizing agent. Suitable oxidizing agents contain a metal and oxygen and are selected from a metal oxide, a metal oxide hydrate, a metal oxide hydroxide, a metal hydrous oxide, a metal hydroxide, or mixtures thereof. The fuel and oxidizing agent are selected such that water vapor is the major gaseous combustion product.

Abstract: An apparatus is disclosed for stage separation and thrust termination in a multi-stage missile having an upper stage detachably connected to a lower stage rocket motor. The apparatus includes a piston located at the forward end of the lower stage rocket motor in fluid communication with the motor's combustion chamber. The piston is configured with a plurality of venting passages, and capable of deployment from a stowed position, in which the venting passages are sealed, to an extended position, in which the venting passages are unsealed. The venting passages are preferably configured to vent the combustion chamber at an angle to the upper stage, providing the lower stage rocket motor with a component of thrust away from the upper stage after detachment without damaging the upper stage. In a preferred embodiment, means for detaching the upper stage includes attachment bolts connecting the stages and explosive detachment charges configured to shear the bolts.

Abstract: Thermoplastic elastomeric ablative insulation having good mechanical properties at extremely low temperatures are disclosed. The insulation is based upon a polyamide-ether resin and includes carefully selected fillers to possess good low temperature mechanical properties and still provide suitable charring and ablative insulation performance at low temperatures (-65.degree. F.). A typical insulation within the scope of the present invention includes a polyamide-ether thermoplastic elastomeric polymer resin, an inorganic phosphorus containing compound, such as ammonium polyphosphate, present in the insulation from about 5 to about 60 phr, and a polyhydric alcohol present, such as pentaerythritol, in the insulation from about 1 to about 30 phr. The insulation compositions within the scope of the present invention optionally include silicone resin present in the insulation in range from about 0 to 15 phr. Chopped fiber filler may also be present in the insulation in range from about 0 to 100 phr.

Abstract: Compositions and methods for increasing the storage life of a propellant grain by reducing the rate of decomposition of its nitrate ester components. A nitrate ester stabilizer is placed in a layer adjacent to a nonburning surface of the propellant grain. The stabilizer migrates from the layer into the grain's nonburning surface to provide additional stabilization for the entire grain, especially portions of the grain adjacent to the protected nonburning surface.