The redesigned RS-25 engine for NASA’s future Space Launch System (SLS) rocket flights was launched February 8 at the agency’s Bay St. Passed the first hot fire test of the year at the Stennis Space Center near St. Louis, Mississippi. The test series supports the production of new RS-25 engines by leading SLS engine manufacturer Aerojet Rocketdyne. The new engines will help power future Artemis missions, starting with Artemis V, as NASA explores the universe for the benefit of all.

The single engine hot ignition on the Fred Haise test stand followed the 2022 confidence test, which checked that everything was ready for the continuation of the certification series.

In the latest test, engineers fired the RS-25 engine for about eight and a half minutes (500 seconds), the time it takes the engines to run to propel the SLS into space. The RS-25 engine also ran at 111% power for most of the test; this was the same level needed to get the SLS into orbit. Tests revealed a number of new components, most of which were installed for the hot fire in December. Another additional component – a new injector – was installed before the last hot fire.

Four RS-25 engines fire simultaneously, producing a total of 1.6 million pounds of thrust during takeoff and 2 million pounds of thrust during ascent to power each SLS flight. NASA and Aerojet Rocketdyne replaced the remaining 16 engines from the flight-approved Space Shuttle Program at Stennis for the Artemis I-IV missions.

Every RS-25 engine to be used by SLS will be tested at NASA Stennis. RS-25 field testing is being conducted by a joint team of operators from NASA, Aerojet Rocketdyne and Syncom Space Services. Syncom Space Services is the prime contractor for Stennis facilities and operations. With the Artemis missions, NASA will land the first woman and the first black human on the lunar surface, paving the way for a long-term presence on the Moon and acting as a stepping stone to Mars.