Abstract: Line Replaceable Unit (LRU) health nodes are provided, as are methods for determining maintenance actions with respect to LRU health nodes. In one embodiment, the LRU health node includes a passive Radio Frequency identification (RFID) module having an RFID memory and an RFID antenna coupled thereto. The LRU health node further includes a mass storage memory, a sensor configured to monitor an operational parameter of an LRU and generate a corresponding output signal, and a health node controller operably coupled to the passive RFID module, to the mass storage memory, and to the sensor. The health node controller is configured to: (i) record the output signal generated by the sensor in the mass storage memory as time-phased sensor data, (ii) derive health summary data from the time-phased sensor data, and (iii) store the health summary data in the RFID memory.

Abstract: Line Replaceable Unit (LRU) health nodes are provided, as are methods for determining maintenance actions with respect to LRU health nodes. In one embodiment, the LRU health node includes a passive Radio Frequency identification (RFID) module having an RFID memory and an RFID antenna coupled thereto. The LRU health node further includes a mass storage memory, a sensor configured to monitor an operational parameter of an LRU and generate a corresponding output signal, and a health node controller operably coupled to the passive RFID module, to the mass storage memory, and to the sensor. The health node controller is configured to: (i) record the output signal generated by the sensor in the mass storage memory as time-phased sensor data, (ii) derive health summary data from the time-phased sensor data, and (iii) store the health summary data in the RFID memory.

Abstract: Systems and methods of controlling solid propellant burn rate, propellant gas pressure, propellant gas pressure pulse shape, and propellant gas flow rate, rely on pulse width modulation of a control valve duty cycle. A control valve that is movable between a closed position and a full-open position is disposed downstream of, and in fluid communication with, a solid propellant gas generator. The solid propellant in the solid propellant gas generator is ignited, to thereby generate propellant gas. The control valve is moved between the closed position and the full-open position at an operating frequency and with a valve duty cycle. The valve duty cycle is the ratio of a time the control valve is in the full-open position to a time it takes the valve to complete one movement cycle at the operating frequency. The valve duty cycle is controlled to attain a desired solid propellant burn rate, propellant gas pressure, propellant gas pressure pulse shape, and/or propellant gas flow rate.

Abstract: Systems and methods of controlling solid propellant burn rate, propellant gas pressure, propellant gas pressure pulse shape, and propellant gas flow rate, rely on the position of a throttling valve. A throttling valve that is movable to a control position is disposed downstream of, and in fluid communication with, a solid propellant gas generator, and in parallel with a plurality of reaction control valves. The solid propellant in the solid propellant gas generator is ignited, to thereby generate propellant gas. The throttling valve is moved to a control position to attain a desired solid propellant burn rate, propellant gas pressure, and/or propellant gas pressure pulse shape.

Abstract: A valve includes a valve body and a free floating poppet. The valve body includes an inlet, an outlet, and a fluid flow passage therebetween. The free floating poppet is disposed in the valve body, and is moveable between at least a closed position, in which the free floating poppet at least substantially restricts fluid from flowing through the fluid flow passage, and an open position, in which fluid is allowed to flow through the fluid flow passage. The free floating poppet includes a base section and a cutback section. The base section has a first cross sectional area. The cutback section has a second cross sectional area that is less than the first cross sectional area.

Abstract: A method is provided for manufacturing a missile component for use in a high temperature environment, where the missile component has a flow passage therethrough and the flow passage has a shape. An apparatus manufactured by the inventive method is provided as well. The method includes the steps of depositing a first metal onto a mandrel having the shape of the flow passage to create a first metal layer, applying an insulating material on to the first metal layer to create an insulating layer, machining a predetermined shape into at least a portion of the insulating layer, and applying a second metal onto the machined insulating layer to create an outer shell layer.

Abstract: A solid rocket motor including a combustion chamber, in which propellant is ignited to produce combustion gas, and a nozzle having a throat with an effective flow area, implements a system and method to inject gas into the nozzle throat to control its effective cross sectional flow area. Controlling the effective cross sectional flow area of the nozzle throat in turn controls combustion chamber pressure, thus the burn rate of the propellant in the combustion chamber, and thus the thrust generated thereby.

Abstract: A valve includes a valve body and a free floating poppet. The valve body includes an inlet, an outlet, and a fluid flow passage therebetween. The free floating poppet is disposed in the valve body, and is moveable between at least a closed position, in which the free floating poppet at least substantially restricts fluid from flowing through the fluid flow passage, and an open position, in which fluid is allowed to flow through the fluid flow passage. The free floating poppet includes a base section and a cutback section. The base section has a first cross sectional area. The cutback section has a second cross sectional area that is less than the first cross sectional area.

Abstract: Systems and methods of controlling solid propellant burn rate, propellant gas pressure, propellant gas pressure pulse shape, and propellant gas flow rate, rely on pulse width modulation of a control valve duty cycle. A control valve that is movable between a closed position and a full-open position is disposed downstream of, and in fluid communication with, a solid propellant gas generator. The solid propellant in the solid propellant gas generator is ignited, to thereby generate propellant gas. The control valve is moved between the closed position and the full-open position at an operating frequency and with a valve duty cycle. The valve duty cycle is the ratio of a time the control valve is in the full-open position to a time it takes the valve to complete one movement cycle at the operating frequency. The valve duty cycle is controlled to attain a desired solid propellant burn rate, propellant gas pressure, propellant gas pressure pulse shape, and/or propellant gas flow rate.

Abstract: A valve comprises a valve body, a poppet, and a pin. The valve body includes an inlet, an outlet, and a fluid flow passage therebetween. The poppet is disposed in the valve body, and is moveable between a closed position, in which the poppet at least substantially restricts fluid from flowing through the fluid flow passage, and an open position, in which fluid is allowed to flow through the fluid flow passage. The pin is disposed in the valve body, and extends at least partially into the poppet. The pin is configured to guide poppet movement in the valve body between the closed position and the open position. In this configuration, the ratio of the poppet length to diameter can be less than one.

Abstract: A vehicle, such as a missile, with a pilot valve system controls the vehicle's thrust valves despite a hostile propellant gas environment. The pilot valve system can have one or more pilot valves. Using refractory elements, the pilot valve ball reciprocates between a supply seat and a vent seat which is subject to the filtered inflow of propellant thrust gases. When open, the pilot valve allows the stray thrust gas to communicate to a control chamber which closes a poppet against a valve seat in the nozzle. When an associated solenoid closes the pilot valve by pushing the pilot valve ball against the supply seat, the control chamber is vented to ambient. The poppet may then travel into the cylinder bore and the nozzle is opened to exhaust propellant gases and exert lateral thrust on the vehicle. Certain nozzle thrust geometries provide useful vehicle guidance.

Abstract: An improved pneumatic valve and a missile with an improved thrust directional valve. In one embodiment, a refractory material lining for a pneumatic valve enables better valve operation and better valve performance. A thin-wall cylindrical sleeve of rhenium or other suitable refractory metal is located inside a cylinder. A valve piston may then travel within the refractory sleeve with greater reliability and better operation. The refractory sleeve cylinder lining can be subject to high temperatures at a rapid rate and remain operational. Under such a hostile environmental, including corrosive/erosive environments created by the passage of hot propellant gasses, the refractory cylinder sleeve has a more reliable operational life and is lighter in weight than conventional valves made entirely of refractory metals.

Abstract: A vehicle, such as a missile, with a pilot valve system controls the vehicle's thrust valves despite a hostile propellant gas environment. The pilot valve system can have one or more pilot valves. Using refractory elements, the pilot valve ball reciprocates between a supply seat and a vent seat which is subject to the filtered inflow of propellant thrust gases. When open, the pilot valve allows the stray thrust gas to communicate to a control chamber which closes a poppet against a valve seat in the nozzle. When an associated solenoid closes the pilot valve by pushing the pilot valve ball against the supply seat, the control chamber is vented to ambient. The poppet may then travel into the cylinder bore and the nozzle is opened to exhaust propellant gases and exert lateral thrust on the vehicle. Certain nozzle thrust geometries provide useful vehicle guidance.

Abstract: An improved pneumatic valve and a missile with an improved thrust directional valve. In one embodiment, a refractory material lining for a pneumatic valve enables better valve operation and better valve performance. A thin-wall cylindrical sleeve of rhenium or other suitable refractory metal is located inside a cylinder. A valve piston may then travel within the refractory sleeve with greater reliability and better operation. The refractory sleeve cylinder lining can be subject to high temperatures at a rapid rate and remain operational.