Abstract: A spacecraft propulsion system includes at least one chemical thruster operable with a liquid propellant, at least one electric thruster operable with an inert gas, and a first quantity ‘n’ of pressurant tanks, each of the ‘n’ pressurant tanks having a substantially identical volume. The propulsion system results from assembling a plurality of subassemblies, such that a first selectable number ‘e’ of the first quantity of pressurant tanks are manifolded together with the at least one electric thruster, and a second selectable number ‘c’ of the first quantity of pressurant tanks are manifolded together with the at least one chemical thruster. The first selectable number ‘e’ is an integer in the inclusive range of 1 to ‘n’, and c=n?e.

Abstract: A spacecraft propulsion system has at least one chemical thruster, at least one electric thruster, a propellant supply arrangement that stores a propellant and a propellant conditioning arrangement configured to convert propellant into chemical species in a thermodynamic phase that can be readily ionized. The propellant is commonly supplied from the propellant storage device to each of the chemical thruster and the electric thruster. The chemical thruster has a gas generator and a high thrust accelerator; the electric thruster has a plasma generator and a high specific impulse accelerator. The propellant supply arrangement is configured to control flow of the propellant from the propellant supply arrangement to the gas generator and the propellant conditioning arrangement, and a first flow path connects propellant supply arrangement with the gas generator, and a second flow path connects propellant supply arrangement with the plasma generator.

Abstract: A spacecraft propulsion system has at least one chemical thruster, at least one electric thruster, a propellant supply arrangement that stores a propellant and a propellant conditioning arrangement configured to convert propellant into chemical species in a thermodynamic phase that can be readily ionized. The propellant is commonly supplied from the propellant storage device to each of the chemical thruster and the electric thruster. The chemical thruster has a gas generator and a high thrust accelerator; the electric thruster has a plasma generator and a high specific impulse accelerator. The propellant supply arrangement is configured to control flow of the propellant from the propellant supply arrangement to the gas generator and the propellant conditioning arrangement, and a first flow path connects propellant supply arrangement with the gas generator, and a second flow path connects propellant supply arrangement with the plasma generator.

Abstract: In a liquid storage tank 10 for use on a spacecraft, a transfer apparatus 15 (comprising gathering vanes 33, an elongate array of fins 32, and a sponge structure formed from panels 31) functions to transfer liquid from the inner surface of the tank 10 to the vicinity of an outlet line 40. A screen 23 is disposed between the panels 31 and the outlet line 40. When wetted with liquid, the screen 23 prevents gas and/or vapor in the tank 10 from passing to the outlet line 40. A perforated plate 22 disposed between the screen 23 and the outlet line 40 causes liquid to pass from the tank 10 to the outlet line 40 in a regular and generally unbroken flow.

Abstract: In a liquid storage tank 10 for use on a spacecraft, a transfer apparatus 15 (comprising gathering vanes 33, an elongate array of fins 32, and a sponge structure formed from panels 31) functions to transfer liquid from the inner surface of the tank 10 to the vicinity of an outlet line 40. A screen 23 is disposed between the panels 31 and the outlet line 40. When wetted with liquid, the screen 23 prevents gas and/or vapor in the tank 10 from passing to the outlet line 40. A perforated plate 22 disposed between the screen 23 and the outlet line 40 causes liquid to pass from the tank 10 to the outlet line 40 in a regular and generally unbroken flow.

Abstract: In a tank 10 for cryogenic liquid to be used in a low-gravity environment (e.g., on a space vehicle), a liquid transfer apparatus 15 (which comprises an elongate array of fins 32 and a sponge structure formed from panels 31) functions to transfer cryogenic liquid from the interior of the tank 10 to a bowl structure 20 defining a reservoir region adjacent an outlet of the tank 10. A perforated plate 22 disposed between the sponge structure and the outlet of the tank 10 causes cryogenic liquid to pass through the outlet into an outlet line 40 in a regular and generally unbroken flow. To prevent any substantial amount of heat transfer into the reservoir region of the tank 10, the bowl structure 20 is separated from the inner surface of the tank 10 by a capillary distance in order to provide a thermally insulating space therebetween.