Provided herein are various improvements to rocket engine components and rocket engine operational techniques. In one example, a rocket engine propellant injection apparatus is provided that includes a manifold formed into a single body by an additive manufacturing process and comprising a fuel cavity and an oxidizer cavity. The manifold also includes one or more propellant feed stubs, the one or more propellant feed stubs protruding from the manifold and formed into the single body of the manifold by the additive manufacturing process, with at least a first stub configured to carry fuel to the fuel cavity and at least a second stub configured to carry oxidizer to the oxidizer cavity. The manifold also includes a plurality of injection features formed by apertures in a face of the manifold, ones of the plurality of injection features configured to inject the fuel and the oxidizer for combustion.

A turbopump includes a turbine fed with hot gas, a pump driven by the turbine and fed with liquid fluid, and a hot gas exhaust pipe situated downstream from the turbine. The turbopump includes a bleed-and-injection circuit including a bleeder for bleeding the liquid fluid at the outlet from the pump, a heater for heating the liquid fluid as bled off in this way so as to transform it into gaseous fluid, and an injector for injecting the gaseous fluid into an interface region of the turbopump situated between the pump and the turbine, so as to optimize the flow and temperature conditions of the fluid entering into the turbine cavity in order to eliminate the vibratory phenomena that result from interaction between the fluid and the turbine disk.

A system for managing propellant and pressurant for in-space propulsion of a spacecraft is provided. The system includes a conformal fuel tank having an ullage operatively connected for pressurization and a propellant management device (PMD) to wick propellant to a liquid port of the conformal fuel tank. The system further includes a pneumatic circuit including a tank pressurant vent valve for adjustment of operating pressure prior to refueling operations; a vent to release excess pressurant; a pressurant metering vent valve to provide control and safety relief for the pressurant; a check valve to prevent backflow; a pressurant cat bed for decomposing propellant into pressurant; a repressurizing valve to release pressurant once cooled; a burst disk to provide overpressure safety relief; a series of propellant extraction valves to intake a predetermined quantity of propellant for decomposition; and a pressure regulator that delivers proper pressure to a series of thrusters.

A dual-mode use Solid Controlled and Hybrid Rocket Engine, in the form of a cord/filament, of variable length, and single or multiple diameters, or shapes, coaxially packaged or comprising at least one, or more, canister-built common use bobbin-propellant housing(s), and at least one, or more, common use rocket engine combustion chamber(s), control feeding(s), and safety feature hardware, for modular-interchangeable space vehicle architectures, built-in variable performance feature-ability, for novel general propulsion uses.

Embodiments of the present invention generally relate to a vapor retention device and methods of using a vapor retention device to manage propellant for upper stage space vehicles. The use of a vapor retention device, in combination with controlled acceleration, drives liquid propellant from a propellant supply line communicating with an upper stage main engine back into a propellant tank and establishes an insulating liquid/gas propellant interface that prevents the exchange of gaseous propellant across the interface.

Provided herein are various improvements to rocket engine components and rocket engine operational techniques. In one example, a rocket engine propellant injection apparatus is provided that includes a manifold formed into a single body by an additive manufacturing process and comprising a fuel cavity and an oxidizer cavity. The manifold also includes one or more propellant feed stubs, the one or more propellant feed stubs protruding from the manifold and formed into the single body of the manifold by the additive manufacturing process, with at least a first stub configured to carry fuel to the fuel cavity and at least a second stub configured to carry oxidizer to the oxidizer cavity. The manifold also includes a plurality of injection features formed by apertures in a face of the manifold, ones of the plurality of injection features configured to inject the fuel and the oxidizer for combustion.

A flow control system (22) includes a fuel passage network (34) that has first (36) and second (38) network portions that are in a parallel flow arrangement with each other. A fueldraulic device (40) is located in the first network portion. Operation of the fueldraulic device varies flow through the first network portion. A flow restriction orifice (42) is located in the fuel passage network and is arranged in series with, and upstream of, the fueldraulic device. The flow restriction orifice is operable to generate a pressure differential that varies responsive to the flow through the first network portion. A flow control valve (44) is located in the second network portion. The flow control valve is operable responsive to the pressure differential across the flow restriction orifice to control flow through the second network portion.

A pogo effect corrector system for a feed system for feeding a rocket engine with liquid propellant, the corrector system comprising: a feed pipe part for feeding liquid propellant that is configured to be connected both upstream and downstream to a liquid propellant feed pipe of the feed system; and a hydraulic accumulator comprising a tank connected to the feed pipe part via at least one communication orifice; the corrector system being characterized in that: at least a portion of the feed pipe part is at least partly surrounded by the inner volume of the tank; with each cross-section of said portion relative to its central axis being at least partly surrounded by the corresponding cross-section of the inner volume of the tank, in such a manner that the corresponding cross-section of the inner volume of the tank is off-center relative to said cross-section of said portion.

A rocket fueling system includes an insulated jacket configured to removably couple to at least a portion of a rocket and form an enclosed space between the insulated jacket and the at least the portion of the rocket. The rocket fueling system also includes a cryogen inlet in the insulated jacket. The cryogen inlet is configured to receive a cryogen into an interior chamber of the insulated jacket. The rocket fueling system further includes a cryogen outlet in the insulated jacket. The cryogen outlet is configured to provide the cryogen from the interior chamber in the insulated jacket to the at least the portion of the rocket in the enclosed space. The rocket fueling system still further includes a gas outlet in the insulated jacket configured to exhaust the cryogen from the enclosed space, and a flammable gas sensor configured to detect a flammable gas at the gas outlet.

A propulsion apparatus is provided with a gas generator and a plurality of thrusters. The gas generator generates combustion gas when a flying body satisfies an emergency condition. Herein, the plurality of thrusters output the combustion gas downward. In addition, when viewed from a direction of travel of the flying body, the plurality of thrusters may overlap the gas generator. Furthermore, the plurality of thrusters may control an attitude of the flying body. In addition, the plurality of thrusters may reduce outputs of the combustion gas to a first output based on a landing of at least a part of the flying body.