NASA marked a key milestone Feb. 18 with installation of RS-25 engine No. E20001, the first new production engine to help power the SLS (Space Launch System) rocket on future Artemis missions to the Moon.

The engine, built by lead SLS engines contractor L3Harris (formerly Aerojet Rocketdyne), was installed on the Fred Haise Test Stand in preparation for acceptance testing next month. It represents the first of 24 new flight engines being built for missions, beginning with Artemis V.

The NASA Stennis test team will conduct a full-duration, 500-second hot fire, providing critical performance data to certify the engine for use on a future mission. 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 Orion spacecraft, into orbit.

The engine arrived at the test stand from the L3Harris Engine Assembly Facility on the engine transport trailer before being lifted onto the vertical engine installer (VEI) on the west side deck. After rolling the engine into the stand, the team used the VEI to raise and secure it in place.

The upcoming acceptance test follows two certification test series that helped verify the new engine production process and components meet all performance requirements. Four RS-25 engines help launch SLS, producing up to 2 million pounds of combined thrust.

All RS-25 engines for Artemis missions are tested and proven flightworthy at NASA Stennis prior to use. RS-25 tests are conducted by a team of operators from NASA, L3Harris, and Syncom Space Services, prime contractor for site facilities and operations.