Chris Bergin - NSF@NASASpaceflightSTATIC FIRE! RS-25 E0525 fires up to make it 12 from 12 in the latest series for future Artemis missions.
Chris Bergin - NSF@NASASpaceflightRS-25 E0525 is the engine that we saw fire up 12 times - full duration - over a short period of time at Stennis. Performed like a champ!
Stennis Space Center@NASAStennis·9mRS-25 developmental engine E0525 was removed from the Fred Haise Test Stand on April 9, following completion of the 2nd (and final) 12-test series for lead engines contractor Aerojet Rocketdyne, an @L3HarrisTech company, to certify and build new RS-25 engines for @NASA_SLS.
Need a lift? 🏗️ NASA Stennis teams conducted a successful lift onto the Fred Haise Test Stand of RS-25 engine No. E20001, the first of 24 new production engines built by lead engines contractor @L3HarrisTech (formerly Aerojet Rocketdyne) to help power the @NASA_SLS (Space Launch System) heavy-lift rocket on future deep-space missions, beginning with @NASAArtemis V. The RS-25 engine will undergo a full-duration, 500-second hot fire test next month, just as during an actual launch, providing critical performance data and ensuring its flightworthiness.During missions to the Moon, RS-25 engines fire for about 500 seconds and up to the 111% power level to help launch SLS, with the @NASA_Orion spacecraft, into orbit.The engine arrived at the test stand on the engine transport trailer before being lifted onto the west side deck and rolled into the stand. Soon, the team will use the engine vertical installer to raise and secure the engine into a thrust frame adapter that provides performance data and holds the engine in place.
I'll go over those pictures and a set of still images of the first new RS-25 flight engine built by L3Harris, which is now installed in the dedicated, single-engine test stand at Stennis Space Center for an upcoming green run/acceptance hot-fire test.
STENNIS SPACE CENTER, Miss., June 24, 2025 — NASA and L3Harris Technologies (NYSE: LHX) have successfully test-fired the first RS-25 rocket engine slated to help power the fifth launch of the Space Launch System or SLS rocket for the Artemis Moon exploration campaign. This is the first hot-fire test of a flight version of the new RS-25 engine. The first four Artemis missions use upgraded RS-25 engines from the space shuttle program.“This successful acceptance test shows that we’ve been able to replicate the RS-25’s performance and reliability, while incorporating modern manufacturing techniques and upgraded components such as the main combustion chamber, nozzle and pogo accumulator assembly,” said Kristin Houston, President, Space Propulsion and Power Systems, Aerojet Rocketdyne, L3Harris. “Our propulsion technology is key to ensuring the United States leads in lunar exploration, creates a sustained presence on the Moon and does not cede this strategic frontier to other nations.”The new L3Harris RS-25 engine throttled up to 111% during the 500-second acceptance test, demonstrating more thrust than what the space shuttle engines required.
June 30, 2025As the thumbnail says, that's the question -- why is NASA now conducting tests in secrecy for something they made a big deal out of not long ago? Conducting RS-25 tests in secret seems to be the latest move by NASA and the White House to conceal work on the stuff that OMB wants terminated. Neither NASA nor the administration has explained what they're doing, and maybe that's part of the plan. Imagery is courtesy of NASA, except where noted.McGregor Live (http://nsf.live/mcgregor) courtesy of NSF/NASASpaceflight, used with permission.Links to social media posts:https://x.com/NASAStennis/status/1775254100575150169https://x.com/nasastennis/status/1775525102878089686 https://x.com/nasastennis/status/1775554913667256631https://x.com/NASAStennis/status/1937227920159744129Links to stories referenced:https://arstechnica.com/space/2025/06/during-a-town-hall-wednesday-nasa-officials-on-stage-looked-like-hostages/00:00 Intro01:00 RS-25 test not even announced until three days after it was conducted03:41 SpaceX is testing its engine hardware more transparently than NASA now07:02 NASA's response to why the test was conducted in secret leaves the questions open08:47 Full footage of the test has finally been released09:31 How long will this secrecy continue?10:27 Thanks for watching!
Jul 5, 2025 #RS25A L3Harris (formerly Aerojet Rocketdyne) RS-25 rocket engine (No. E20001) was tested on the Fred Haise Test Stand (formerly A-1 Test Stand) at the John C. Stennis Space Center in Mississippi, on 20 June 2025. According to NASA, the RS-25 engine No. E20001 is “the first new production engine to help power the SLS (Space Launch System) rocket on future Artemis missions to the Moon”. During the full duration test (500 seconds), the engine was fired up to the 111% power level, the same amount of thrust needed during the SLS launch with the Orion spacecraft.Credit: NASA/Danny Nowlin
