Communications Strategist

Oct 21, 2026

NASA tested RS-25 engine No. 10001 on Oct. 21 on the Fred Haise Test Stand at NASA’s Stennis Space Center near Bay St. Louis, Mississippi.

Test teams fired the developmental engine for almost eight-and-a-half minutes (500 seconds), the same amount of time RS-25 engines fire during launch of NASA’s SLS (Space Launch System) rocket.

During the test, operators also fired the engine up to the 111% power level, matching the thrust needed for new production engines to launch the SLS rocket and the Orion spacecraft to orbit.

The main objectives of the test were to acceptance test RS-25 flight components for future Artemis missions and validate the new thermal protection system, which protects the RS-25 engine nozzle from the thermal environment surrounding SLS during launch.

While this developmental engine will not be used in flight, the hot fire test provides NASA and NASA’s prime contractor L3Harris Technologies with the capability to capture critical data to improve…