L3Harris ships SLS core stage engines for Artemis III mission

KENNEDY SPACE CENTER, Fla. — L3Harris Technologies has delivered the four RS-25 engines that will power the core stage of NASA’s Space Launch System for Artemis III, a mission targeted for 2027.

“This is a major milestone in our effort to return astronauts to the lunar surface,” said Kristin Houston, President, Space Propulsion & Power Systems, Missile Solutions, L3Harris. “This delivery keeps Artemis III on track for launch in 2027 and supports NASA’s transition to an annual launch cadence that will enable regular missions to the Moon.”

Artemis III is planned as the third SLS flight and will test integrated operations between the Orion spacecraft and one or both commercial lunar landers in low Earth orbit. The mission will also introduce a new approach to engine installation: technicians will integrate the RS-25s with the core stage in a vertical position for the first time, a shift intended to streamline the process and improve access to each engine.

The four engines assigned to Artemis III previously supported 36 space shuttle flights, including International Space Station assembly missions and the return to space of Project Mercury astronaut and former Sen. John Glenn. For the first four Artemis missions, L3Harris has upgraded the RS-25s with modern electronics and new insulation to withstand the SLS thermal environment; the engines will operate at higher thrust levels than during the shuttle era.

Missions that follow will transition to newly built RS-25s incorporating modern manufacturing techniques and other enhancements aimed at reducing costs while maintaining performance and reliability.