Aerojet Rocketdyne refurbishing RS-25 engines for Artemis 1 launch and production restart testing April 9, 2021 With the completion of another single-engine RS-25 development test, Aerojet Rocketdyne is now refurbishing five engines at the Stennis Space Center in Mississippi for their next use. After the second test firing of the Retrofit 2 series in the A-1 Test Stand on April 6, development engine 0528 is going through a streamlined refurbishment prior to its next firing as a part of the production restart Retrofit 2 test series. In parallel, the four RS-25 engines installed on the first Space Launch System (SLS) Core Stage in the nearby B Test Stand are being taken through a longer refurbishment checklist for flight engine hardware. The next planned ignition for those Core Stage engines is for the first SLS launch on the Artemis 1 mission to send an Orion spacecraft to lunar orbit.