In spacecraft propulsion, a Hall-effect thruster (HET) is a type of ion thruster in which the propellant is accelerated by an electric field. Hall-effect thrusters are sometimes referred to as Hall thrusters or Hall-current thrusters. Hall-effect thrusters use a magnetic field to limit the electrons' axial motion and then use them to ionize propellant, efficiently accelerate the ions to produce thrust, and neutralize the ions in the plume. The Hall-effect thruster is classed as a moderate specific impulse space propulsion technology and has benefited from considerable theoretical and experimental research since the 1960s.
A hypergolic propellant is a rocket propellant combination used in a rocket engine, whose components spontaneously ignite when they come into contact with each other.
The expander cycle is a power cycle of a bipropellant rocket engine. In this cycle, the fuel is used to cool the engine's combustion chamber, picking up heat and changing phase. The now heated and gaseous fuel then powers the turbine that drives the engine's fuel and oxidizer pumps before being injected into the combustion chamber and burned.
Aerojet Rocketdyne is a subsidiary of American defense company L3Harris Technologies that manufactures rocket, hypersonic, and electric propulsive systems for space, defense, civil and commercial applications. Aerojet traces its origins to the General Tire and Rubber Company established in 1915, while Rocketdyne was created as a division of North American Aviation in 1955. Aerojet Rocketdyne was formed in 2013 when Aerojet and Pratt & Whitney Rocketdyne were merged, following the latter's acquisition by GenCorp from Pratt & Whitney. On April 27, 2015, the name of the holding company, GenCorp Inc., was changed to Aerojet Rocketdyne Holdings, Inc. Aerojet Rocketdyne Holdings was acquired by L3Harris in July 2023 for $4.7 billion.
A reaction control system (RCS) is a spacecraft system that uses thrusters to provide attitude control and translation. Alternatively, reaction wheels are used for attitude control. Use of diverted engine thrust to provide stable attitude control of a short-or-vertical takeoff and landing aircraft below conventional winged flight speeds, such as with the Harrier "jump jet", may also be referred to as a reaction control system.
The staged combustion cycle is a power cycle of a bipropellant rocket engine. In the staged combustion cycle, propellant flows through multiple combustion chambers, and is thus combusted in stages. The main advantage relative to other rocket engine power cycles is high fuel efficiency, measured through specific impulse, while its main disadvantage is engineering complexity.
The pressure-fed engine is a class of rocket engine designs. A separate gas supply, usually helium, pressurizes the propellant tanks to force fuel and oxidizer to the combustion chamber. To maintain adequate flow, the tank pressures must exceed the combustion chamber pressure.
Aerojet was an American rocket and missile propulsion manufacturer based primarily in Rancho Cordova, California, with divisions in Redmond, Washington, Orange and Gainesville in Virginia, and Camden, Arkansas. Aerojet was owned by GenCorp. In 2013, Aerojet was merged by GenCorp with the former Pratt & Whitney Rocketdyne to form Aerojet Rocketdyne.
Spacecraft electric propulsion is a type of spacecraft propulsion technique that uses electrostatic or electromagnetic fields to accelerate mass to high speed and thus generate thrust to modify the velocity of a spacecraft in orbit. The propulsion system is controlled by power electronics.
The AJ10 is a hypergolic rocket engine manufactured by Aerojet Rocketdyne. It has been used to propel the upper stages of several launch vehicles, including the Delta II and Titan III. Variants were and are used as the service propulsion engine for the Apollo command and service module, in the Space Shuttle Orbital Maneuvering System, and on the European Service Module – part of NASA's Orion spacecraft.
The pintle injector is a type of propellant injector for a bipropellant rocket engine. Like any other injector, its purpose is to ensure appropriate flow rate and intermixing of the propellants as they are forcibly injected under high pressure into the combustion chamber, so that an efficient and controlled combustion process can happen.
The RL60 was a planned liquid-fuel cryogenic rocket engine designed in the United States by Pratt & Whitney, burning cryogenic liquid hydrogen and liquid oxygen propellants. The engine runs on an expander cycle, running the turbopumps with waste heat absorbed from the main combustion process. This high-efficiency, waste heat based combustion cycle combined with the high-performance liquid hydrogen fuel enables the engine to reach a very high specific impulse of up to 465 seconds in a vacuum. The engine was planned to be a more capable successor to the Aerojet Rocketdyne RL10, providing improved performance and efficiency while maintaining the installation envelope of the RL10.
The descent propulsion system or lunar module descent engine (LMDE), internal designation VTR-10, is a variable-throttle hypergolic rocket engine invented by Gerard W. Elverum Jr. and developed by Space Technology Laboratories (TRW) for use in the Apollo Lunar Module descent stage. It used Aerozine 50 fuel and dinitrogen tetroxide oxidizer. This engine used a pintle injector, which paved the way for other engines to use similar designs.
The TR-201 or TR201 is a hypergolic pressure-fed rocket engine used to propel the upper stage of the Delta rocket, referred to as Delta-P, from 1972 to 1988. The rocket engine uses Aerozine 50 as fuel, and N
2O
4 as oxidizer. It was developed in the early 1970s by TRW as a derivative of the lunar module descent engine (LMDE). This engine used a pintle injector first invented by Gerard W. Elverum Jr. and developed by TRW in the late 1950s and received US Patent in 1972. This injector technology and design is also used on SpaceX Merlin engines.
The ascent propulsion system (APS) or lunar module ascent engine (LMAE) is a fixed-thrust hypergolic rocket engine developed by Bell Aerosystems for use in the Apollo Lunar Module ascent stage. It used Aerozine 50 fuel, and N
2O
4 oxidizer. Rocketdyne provided the injector system, at the request of NASA, when Bell could not solve combustion instability problems.
The Green Propellant Infusion Mission (GPIM) was a NASA technology demonstrator project that tested a less toxic and higher performance/efficiency chemical propellant for next-generation launch vehicles and CubeSat spacecraft. When compared to the present high-thrust and high-performance industry standard for orbital maneuvering systems, which for decades, have exclusively been reliant upon toxic hydrazine based propellant formulations, the "greener" hydroxylammonium nitrate (HAN) monopropellant offers many advantages for future satellites, including longer mission durations, additional maneuverability, increased payload space and simplified launch processing. The GPIM was managed by NASA's Marshall Space Flight Center in Huntsville, Alabama, and was part of NASA's Technology Demonstration Mission Program within the Space Technology Mission Directorate.
Laser ignition is an alternative method for igniting mixtures of fuel and oxidiser. The phase of the mixture can be gaseous or liquid. The method is based on laser ignition devices that produce short but powerful flashes regardless of the pressure in the combustion chamber. Usually, high voltage spark plugs are good enough for automotive use, as the typical compression ratio of an Otto cycle internal combustion engine is around 10:1 and in some rare cases reach 14:1. However, fuels such as natural gas or methanol can withstand high compression without autoignition. This allows higher compression ratios, because it is economically reasonable, as the fuel efficiency of such engines is high. Using high compression ratio and high pressure requires special spark plugs that are expensive and their electrodes still wear out. Thus, even expensive laser ignition systems could be economical, because they would last longer.
A liquid apogee engine (LAE), or apogee engine, refers to a type of chemical rocket engine typically used as the main engine in a spacecraft.
The MARC-60, also known as MB-60, MB-XX, and RS-73, is a liquid-fuel cryogenic rocket engine designed as a collaborative effort by Japan's Mitsubishi Heavy Industries and US' Aerojet Rocketdyne. The engine burns cryogenic liquid oxygen and liquid hydrogen in an open expander cycle, driving the turbopumps with waste heat from the main combustion process.
The Hispasat 1B was a Spanish communications satellite operated by Hispasat. Along with the Hispasat 1A, the satellite covered communications over the American Continent for both civilian and military customers. Together they formed the first European constellation operating over the New World. Its service life ended in 2003.
