Abstract: Systems and methods for passive and active hybrid defrost control for a pool/spa heat pump are provided. The system monitors the temperature of the evaporator coil of the heat pump and, as required, operates the heat pump in a passive defrost mode if the temperature is less than or equal to a first predetermined temperature value. The system operates the heat pump in an active defrost mode if the temperature of the evaporator coil remains below the first predetermined temperature value and a first time period has expired. The system can stop operation of the active defrost mode when the temperature of the evaporator coil is greater than a second predetermined temperature value. Additionally, the system can stop operation of the passive defrost mode or the active defrost mode upon expiration of a timeout timer.

Abstract: A swimming pool or spa heat pump operable in cooling and heating modes, along with a method of operating same is disclosed. The heat pump includes a compressor, first and second heat exchangers, refrigerant charge compensator, and at least one means for lowering the pressure of refrigerant provided to the first and second heat exchangers. The first heat exchanger is configured to transfer thermal energy to and/or extract thermal energy from a first fluid, and the second heat exchanger is configured to transfer thermal energy to and/or extract thermal energy from pool or spa water. The refrigerant charge compensator is configured to reduce an amount of active refrigerant charge in circulation in the heat pump when the heat pump is operated in the cooling mode and increase the amount of active refrigerant charge in circulation when the heat pump is operated in the heating mode.

Abstract: A damper system for a pyrotechnic time delay may comprise: a firing pin; a moveable housing defining a chamber therein; a fixed piston comprising a piston head disposed in the chamber, a first rod extending from the piston head axially outward of the moveable housing, and a second rod configured to fixedly couple to a housing; a first spring extending axially from the moveable housing to the firing pin; and a second spring extending axially from the moveable housing to the firing pin.

Abstract: The present invention relates to an aliphatic-aromatic polyester having a whiteness index according to ASTM E 313-73 of at least 25, to a process for preparation thereof and to the use of the aliphatic-aromatic polyester for production of polyester fibers (PF). The present invention further relates to the polyester fibers (PF) comprising the aliphatic-aromatic polyester.

Abstract: A solid-propellant gas generator assembly may comprise a bulkhead having an orifice disposed in a housing. The bulkhead may be disposed between a first end and a second end of the housing. The bulkhead and the first end may define a propellant cavity. The bulkhead and the second end may define a pressure chamber. A fast burning solid-propellant may be disposed in the propellant cavity. The solid-propellant gas generator assembly may be configured to replace a slow burning solid-propellant gas generator system in a solid-propellent gas generator system.

Abstract: A high energy catapult assembly may comprise an outer tube and an inner tube located within the outer tube. The outer tube may be configured to telescope relative to the inner tube. A propellant cartridge may be located in an inner tube chamber of the inner tube. An actuator may be configured to change an open volume of the inner tube chamber.

Abstract: A high energy catapult assembly may comprise an outer tube and an inner tube located within the outer tube. The outer tube may be configured to telescope relative to the inner tube. A propellant cartridge may be located in an inner tube chamber of the inner tube. An actuator may be configured to change an open volume of the inner tube chamber.

Abstract: A method for non-destructively determining a mechanical property of a solid rocket motor propellant grain may comprise applying a force to a surface of the solid rocket motor propellant grain, wherein a deformation is formed on the surface of the solid rocket motor propellant grain in response to the applying, and calculating a value of the mechanical property of the solid rocket motor propellant grain based on the deformation. The force may be applied by moving a liquid into the perforation. This process may be performed over time to determine a lifespan of the propellant grain.

Abstract: A method for non-destructively determining a mechanical property of a solid rocket motor propellant grain may comprise applying, via a gas, a force to a surface of the solid rocket motor propellant grain, wherein a deformation is formed on the surface of the solid rocket motor propellant grain in response to the applying, and measuring a pressure of the gas. This process may be performed over time to determine a lifespan of the propellant grain.

Abstract: A method for non-destructively determining a mechanical property of a solid rocket motor propellant grain may comprise applying a force to a surface of the solid rocket motor propellant grain, wherein a deformation is formed on the surface of the solid rocket motor propellant grain in response to the applying, and calculating a value of the mechanical property of the solid rocket motor propellant grain based on the deformation. This process may be performed over time to determine a lifespan of the propellant grain.

Abstract: A method for non-destructively determining a mechanical property of a solid rocket motor propellant grain may comprise applying a force to a surface of the solid rocket motor propellant grain, wherein a deformation is formed on the surface of the solid rocket motor propellant grain in response to the applying, and calculating a value of the mechanical property of the solid rocket motor propellant grain based on the deformation. This process may be performed over time to determine a lifespan of the propellant grain.

Abstract: A solid-propellant gas generator assembly may comprise a bulkhead having an orifice disposed in a housing. The bulkhead may be disposed between a first end and a second end of the housing. The bulkhead and the first end may define a propellant cavity. The bulkhead and the second end may define a pressure chamber. A fast burning solid-propellant may be disposed in the propellant cavity. The solid-propellant gas generator assembly may be configured to replace a slow burning solid-propellant gas generator system in a solid-propellent gas generator system.

Abstract: An inflation system is disclosed. In various embodiments, the inflation system includes a solid-propellant gas generator; and a gas motor having a turbine coupled to the solid-propellant gas generator and a compressor configured for coupling to an inflatable device.

Abstract: The present disclosure provides a high explosive firing mechanism. The high explosive firing mechanism may comprise a housing comprising a firing pin tube having a primer inlet. The high explosive firing mechanism may further comprise a firing pin disposed within the firing pin tube, the firing pin comprising a nub. The nub may partially extend into the primer inlet.

Abstract: A method for non-destructively determining a mechanical property of a solid rocket motor propellant grain may comprise applying a force to a surface of the solid rocket motor propellant grain, wherein a deformation is formed on the surface of the solid rocket motor propellant grain in response to the applying, and calculating a value of the mechanical property of the solid rocket motor propellant grain based on the deformation. This process may be performed over time to determine a lifespan of the propellant grain.

Abstract: A method for non-destructively determining a mechanical property of a solid rocket motor propellant grain may comprise applying a force to a surface of the solid rocket motor propellant grain, wherein a deformation is formed on the surface of the solid rocket motor propellant grain in response to the applying, and calculating a value of the mechanical property of the solid rocket motor propellant grain based on the deformation. This process may be performed over time to determine a lifespan of the propellant grain.

Abstract: A method for non-destructively determining a mechanical property of a solid rocket motor propellant grain may comprise applying, via a gas, a force to a surface of the solid rocket motor propellant grain, wherein a deformation is formed on the surface of the solid rocket motor propellant grain in response to the applying, and measuring a pressure of the gas. This process may be performed over time to determine a lifespan of the propellant grain.

Abstract: A method for non-destructively determining a mechanical property of a solid rocket motor propellant grain may comprise applying a force to a surface of the solid rocket motor propellant grain, wherein a deformation is formed on the surface of the solid rocket motor propellant grain in response to the applying, and calculating a value of the mechanical property of the solid rocket motor propellant grain based on the deformation. The force may be applied by moving a liquid into the perforation. This process may be performed over time to determine a lifespan of the propellant grain.