Abstract: Solid propellant systems include a main propellant and a secondary propellant in contact with the first propellant that exhibits autoignition temperatures of at least about 100° F. lower than the autoignition temperature of the main propellant. The secondary propellant of the present invention is most advantageously employed with conventional AP-containing solid propellant formulations as the main propellant, especially formulations containing both AP, an energetic solid, and a binder. In especially preferred forms, the secondary propellant will include a nitramine which is at least one selected from nitroguanidine (NQ), cyclotrimethylene trinitramine (RDX) and cyclotetramethylenetetranitramine (HMX), and a binder which is at least one selected from HTPB, HTPE or glycidyl azide polymer (GAP). Most preferably, the secondary propellant will include a combination of nitramines which includes NQ and one of RDX or HMX.

Abstract: Solid propellant systems include a main propellant and a secondary propellant in contact with the first propellant that exhibits autoignition temperatures of at least about 100° F. lower than the autoignition temperature of the main propellant. The secondary propellant of the present invention is most advantageously employed with conventional AP-containing solid propellant formulations as the main propellant, especially formulations containing both AP, an energetic solid, and a binder. In especially preferred forms, the secondary propellant will include a nitramine which is at least one selected from nitroguanidine (NQ), cyclotrimethylene trinitramine (RDX) and cyclotetramethylenetetranitramine (HMX), and a binder which is at least one selected from HTPB, HTPE or glycidyl azide polymer (GAP). Most preferably, the secondary propellant will include a combination of nitramines which includes NQ and one of RDX or HMX.

Abstract: High thrust at sea level and high Isp at high altitudes with low ambient pressure are obtained in a vehicle with an engine of fixed geometry including an exit of non-changing cross section, by incorporating a series of propellant injectors in a divergent section of the engine, spaced apart along the engine axis at points of different engine cross section. At takeoff, the injectors at sites with a large cross section are used, and as the vehicle climbs, these injectors are successively closed leaving injectors activated at sites of successively smaller cross sections. The injectors establish thermal choke points, and the area ratio of the cross section at the exit to the cross section at the thermal choke point thus increases as the vehicle climbs from low to high altitudes.

Abstract: An engine that operates and produces the entire required vehicle thrust below Mach 4 is useful for a Hypersonic combined cycle vehicle by saving vehicle and engine development costs. One such engine is a combined cycle engine having both a booster and a dual mode ramjet (DMRJ). The booster and the DMRJ are integrated to provide effective thrust from Mach 0 to in excess of Mach 4. As the booster accelerates the vehicle from Mach 0 to in excess of Mach 4, from Mach 0 to about Mach 2 incoming air delivered to the DMRJ is accelerated by primary ejector thrusters that may receive oxidizer from either on-board oxidizer tanks or from turbine compressor discharge air. As the TBCC further accelerates the vehicle from about Mach 0 to in excess of Mach 4 exhaust from the turbine and exhaust from the DMRJ are combined in a common nozzle disposed downstream of a combustor portion of said DMRJ functioning as an aerodynamic choke.

Abstract: An inducer includes a hub having an inlet end and an outlet end. At least one full size blade has an inner edge is affixed to the hub and an outer edge. This full size blade extends rearwardly from the inlet end in a helical configuration. A partial shroud encloses a first length of the full size blade outer edge adjacent the inlet end. A second length of the full size blade outer edge that is adjacent to the outlet end is free of the partial shroud. It is within the scope of the disclosure to include short blades symmetrically offset from the two full size blades. These short blades have a short blade inner end affixed to the partial shroud and a short blade outer end extending from the partial shroud towards the hub, but terminating prior to reaching the hub.

Abstract: A cloud of small to medium-sized space debris is mitigated by releasing drag-reducing particles into the cloud from a dispenser vehicle, causing the particles to collide or otherwise interact with, and thereby exchange momentum with, the debris particles, reducing the orbiting velocity of the debris to a degree sufficient to cause the debris to de-orbit, or to accelerate the de-orbiting of the debris, to Earth. Certain embodiments also include a shepherd vehicle containing systems for identifying and tracking the debris cloud and for coalescing the debris cloud to increase the particles density in the cloud.

Abstract: A composite is produced by the steps of (a) blending a first mixture of metallic powders; (b) compacting the blended first mixture of metallic powders to a plurality of discretely shaped articles; (c) blending a second mixture of metallic powders; (d) mixing the plurality of discretely shaped articles with the blended second mixture of metallic powders to form a precursor blend; (e) compacting the precursor blend; and (f) sintering the precursor blend. The composite has a metallic matrix with embedded shapes dispersed throughout the matrix where the embedded shapes have an incipient liquid phase sintering temperature less than an incipient liquid phase sintering temperature of the matrix.

Abstract: An end-burning grain of a solid rocket motor or other gas-generating device is supplemented with one or more sticks of high-burn-rate propellant embedded in a matrix of a relatively low-burn-rate propellant. The sticks increase the burning surface area as the grain burns by forming conical indentations in the surface.

Abstract: A stove includes a combustion chamber for producing heat, a thermoelectric device thermally coupled to a hot source and a cold source, a battery, a fan electrically connected to the thermoelectric device and the battery, and a controller configured to monitor the battery and thermoelectric device and configured to direct the fan be operated from power provided from the battery when power produced from the thermoelectric device is insufficient to power the fan. The stove can have an associated heating plate, and the walls of the combustion chamber can be configured to reflect heat onto the heating plate.

Abstract: A stove includes a combustion chamber for producing heat, a thermoelectric device thermally coupled to a hot source and a cold source, a battery, a fan electrically connected to the thermoelectric device and the battery, and a controller configured to monitor the battery and thermoelectric device and configured to direct the fan be operated from power provided from the battery when power produced from the thermoelectric device is insufficient to power the fan.

Abstract: A catalyst includes a carrier of essentially hafnia, up to an equal part zirconia, and optionally additional stabilizers, upon the surface of which is deposited an active metal suitable to promote the reaction of propellants to be used in gas generators and thrusters.

Abstract: A multi-pulse rocket is equipped with a thermally insulating barrier that serves as a rupture disk or a movable plug or plate separating staged propellant grains. When a rupture disk it used, the disk can be equipped with a pyrotechnic actuator to weaken the disk upon command, enabling the propellant grain on the fore side of the disk to burst the disk at a relatively low pressure when ignition of the propellant grain is needed for additional thrust. Rupturing of the disk can also be controlled by attitude maneuvering ports on the fore side of the barrier whose open or closed conditions are controlled by independently operable closures. When a movable plug is used, the plug is movable between a closed position separating rocket chamber into subchambers isolating the propellant grains from each other and an open position allowing the flow of combustion gas between the two subchambers to achieve additional axial thrust.

Abstract: Improved rocket nozzle designs for vehicles with nozzles embedded in or protruding from surfaces remote from the desired thrust axis. The nozzle configurations are for rocket vehicles where the nozzles are not located at the optimal thrust axis of the vehicle. Two examples include nozzles located on the forward end of the vehicle (also called tractor nozzles) and attitude control nozzles located on the periphery of the vehicle. More particularly, the disclosed nozzle shapes enhance the axial thrusts and/or maneuver torques on the vehicle. These unconventional nozzle shapes improve vehicle performance.

Abstract: A polymer adhesive includes a polymeric binder, optional reinforcing fibers dispersed through the polymer binder and solids dispersed in the polymeric binder. The solids are effective to cause decomposition of the polymer adhesive at a temperature between 200° F. and 500° F. with a generation of gaseous products at a predetermined temperature. One suitable composition includes siloxirane, graphite, glass beads, potassium nitrate, silver nitrate and lactose and decomposes at a temperature of about 318° F. The polymer adhesive may be used in the assembly of a housing for rocket motor or a warhead. Decomposition of the polymer adhesive when the housing is exposed to sufficient external heat to cause a rocket propellant or warhead explosive to decompose, referred to as cook-off, enables venting of the rocket propellant or warhead without uncontrolled destructive rupture of the housing.

Abstract: Improved rocket nozzle designs for vehicles with nozzles embedded in or protruding from surfaces remote from the desired thrust axis. The nozzle configurations are for rocket vehicles where the nozzles are not located at the optimal thrust axis of the vehicle. Two examples include nozzles located on the forward end of the vehicle (also called tractor nozzles) and attitude control nozzles located on the periphery of the vehicle. More particularly, the disclosed nozzle shapes enhance the axial thrusts and/or maneuver torques on the vehicle. These unconventional nozzle shapes improve vehicle performance.

Abstract: A propulsion system with a divergent-convergent nozzle is provided with variable thrust by a pintle whose position relative to the nozzle throat is controlled by an actuator that includes a rotor that external to, and encircling, the nozzle, and that is coupled to either the pintle or to the nozzle shell by a linkage that translates the rotary movement of the rotor into linear movement of either the pintle or the shell.

Abstract: A multi-pulse rocket is equipped with a thermally insulating barrier that serves as a rupture disk or a movable plug or plate separating staged propellant grains. When a rupture disk it used, the disk can be equipped with a pyrotechnic actuator to weaken the disk upon command, enabling the propellant grain on the fore side of the disk to burst the disk at a relatively low pressure when ignition of the propellant grain is needed for additional thrust. Rupturing of the disk can also be controlled by attitude maneuvering ports on the fore side of the barrier whose open or closed conditions are controlled by independently operable closures. When a movable plug is used, the plug is movable between a closed position separating rocket chamber into subchambers isolating the propellant grains from each other and an open position allowing the flow of combustion gas between the two subchambers to achieve additional axial thrust.

Abstract: Catalyst beds for monopropellant propulsion systems are heated by resistance heating through a conductive material that is incorporated in the catalyst bed and a pair of electrodes on opposite sides of the bed. Imposition of a voltage across the electrodes to heat the bed is performed at will without consumption of any heating components, and heating of the bed is achieved rapidly and uniformly across the entire bed.

Abstract: A solid propellant fire extinguisher or a hybrid fire extinguisher is incorporated into a vehicle fire suppression system. The system is activated according to at least one condition selected from the group consisting of acceleration, deceleration, speed, time, temperature, fuel, fuel level, fire, smoke, light transmittance and optical signature.

Abstract: An engine that operates and produces the entire required vehicle thrust below Mach 4 is useful for a Hypersonic combined cycle vehicle by saving vehicle and engine development costs. One such engine is a combined cycle engine having both a booster and a dual mode ramjet (DMRJ). The booster and the DMRJ are integrated to provide effective thrust from Mach 0 to in excess of Mach 4. As the booster accelerates the vehicle from Mach 0 to in excess of Mach 4, from Mach 0 to about Mach 2 incoming air delivered to the DMRJ is accelerated by primary ejector thrusters that may receive oxidizer from either on-board oxidizer tanks or from turbine compressor discharge air. As the TBCC further accelerates the vehicle from about Mach 0 to in excess of Mach 4 exhaust from the turbine and exhaust from the DMRJ are combined in a common nozzle disposed downstream of a combustor portion of said DMRJ functioning as an aerodynamic choke.