NASA tested RS‑25 engine No. 10001 on Oct. 21, 2026, at the Fred Haise Test Stand at Stennis Space Center to exercise new components for future Artemis missions, the agency reported.
Test teams fired the developmental engine for almost eight‑and‑a‑half minutes, a 500‑second burn that matches the RS‑25 burn time during SLS launches. Operators also pushed the engine to the 111% power level to match thrust expectations for new production engines that will lift NASA’s SLS rocket and Orion spacecraft.
NASA said the run validated a new thermal protection system for the engine nozzle. The agency and prime contractor L3Harris Technologies will use the data to improve performance and reliability, though the tested engine is developmental and will not fly.
