Propulsion and Energy

Many companies and agencies achieve new launch capabilities with more to come

The Liquid Propulsion Technical Committee works to advance reaction propulsion engines employing liquid or gaseous propellants.

NASA’s Stennis Space Center in Mississippi conducted a series of green run tests of the first Space Launch System core stage, culminating with a hot fire of the stage’s four RS-25 engines in March. It marked the most powerful test conducted at Stennis in more than 40 years. In addition, Stennis conducted a series of RS-25 single-engine tests, collecting data for production of new engines for future SLS missions. The site also continued testing work with companies such as Relativity Space, Virgin Orbit and Launcher, all based in California, and Firehawk Aerospace of Florida.

Virgin Orbit conducted its first commercial launch in June when LauncherOne, a two-stage expendable RP-1/liquid oxygen rocket, was dropped from the wing of a modified Boeing 747. Virgin Galactic’s first fully crewed flight with SpaceShipTwo VSS Unity was launched into suborbital space in July. SpaceShipTwo uses a hybrid nitrous oxide/hydroxyl-terminated polybutadiene rocket motor. In July, Blue Origin completed New Shepard’s first human flight with four passengers on board, passing the Kármán line. Powering this flight was the BE-3PM, a liquid hydrogen/LOx engine designed for restart and deep throttle operation.

NASA awarded its Human Landing System contract to SpaceX, with Starship intended to take astronauts from lunar orbit to the surface of the moon. A three-engine prototype was launched and landed in May. Alabama-based Dynetics also completed significant development testing milestones on its lunar lander propulsion system prior to the contract down-select in April, including taking the full design to preliminary design review-level maturity.

The European Space Agency awarded ArianeGroup a contract in July to develop a new kick stage called Astris for the Ariane 6 launcher. Astris will be powered by a 5 kilonewton storable hypergolic nitrogen tetroxide/monomethylhydrazine engine. A demonstrator of this engine, SPE/Berta, was predeveloped in the frame of ESA’s Future Launcher Preparatory Program. First hot fire tests were completed in August.

In February, the German Aerospace Center, or DLR, received the first upper stage of the European Ariane 6 launcher. The fully functional test module was subjected to extensive testing at DLR’s Lampoldshausen P5.2 test stand. This stand is one of the largest projects in the history of the DLR site and will allow DLR to qualify not only engines and individual components but also entire cryogenic upper stages.

In May, Prometheus motor M1, the first European LOx/methane precursor engine, entered assembly and integration. An upgraded motor version with a 20% increase in thrust is under development.

Isar Aerospace Technologies GmbH was announced as winner of the main round of the German microlauncher competition in April. The company will receive $12.8 million for qualification and two demonstration flights of its Spectrum launcher.

Stellar Exploration of California supplied a novel micropump-fed cubesat propulsion system that was used to raise the orbit of an Echo Star spacecraft. This system featured a California-based Flight Works-developed electric micropump that was used to power the eight small hydrazine thrusters. NASA’s CAPSTONE, short for Cislunar Autonomous Positioning System Technology Operations and Navigation Experiment, and Lunar Flashlight CubeSat missions will use similar micropumps.

ZBOT-NC, the second in series of the Zero Boil-Off Tank Experiments, passed its preliminary design review. NASA’s Glenn Research Center in Ohio is developing this microgravity experiment to investigate the effect of noncondensable gases on propellant tank self-pressurization and pressure control.

Contributors: Eric Besnard, Miranda Caserta, David Coote, Andy Crocker, Mohammad Kassemi, Christoph Kirchberger, Anne Lekeux, Bogdan Marcu, Ken Philippart and Dieter Preclik

Many companies and agencies achieve new launch capabilities with more to come