NASA completes full-duration ‘hot fire’ test of new RS-25 engine
by Sheri Walsh
Washington DC (UPI) Jun 23, 2025
NASA fired up a full-duration test of its new RS-25 engine that will power the Space Launch System rocket on Artemis missions to the moon, the space agency announced Monday.
NASA tested RS-25 engine No. 20001 on Friday at the Fred Haise Test Stand at NASA’s Stennis Space Center at Bay St. Louis in Mississippi. The full-duration “hot fire” test was the first since NASA completed certification testing for new production RS-25 engines last year.
The engine, built by contractor L3Harris Technologies — formerly Aerojet Rocketdyne — was fired up for nearly eight-and-a-half minutes. That is the same amount of time it would take four RS-25 engines to launch an SLS rocket, sending astronauts aboard the Orion into orbit. The engine was also fired up to the 111% power level to test its limits.
The test was conducted by a team from NASA, L3Harris and Syncom Space Services, which is the contractor for site facilities. All RS-25 engines are being tested and proven flightworthy at NASA Stennis after the space agency completed its RS-25 certification test series in April 2024.
“The newly produced engines on future SLS rockets will maintain the high reliability and safe flight operational legacy the RS-25 is known for while enabling more affordable high-performance engines for the next era of deep space exploration,” Johnny Heflin, SLS liquid engines manager, said last year.
The RS-25 engine dates back to the 1960s, with a previous iteration of Rocketdyne from the 1970s. NASA’s first space shuttle flight used RS-25 engines to launch in April 1981.
It will take four RS-25 engines, producing a combined 8.8 million pounds of thrust at liftoff, to launch the SLS rocket for Artemis missions.
NASA is targeting the first crewed Artemis mission, Artemis II, for April 2026. It will be the first crewed mission beyond low Earth orbit since Apollo 17 in 1972. During Artemis II, four astronauts will make a trip around the moon. Artemis III will include a lunar landing, which is currently scheduled for 2027.
Related Links
Rocket Science News at Space-Travel.Com
