Green Run Update: SLS Team Prepares Core Stage for Second Hot Fire Test

The core stage Green Run test team has completed refurbishment activities and is preparing the Space Launch System (SLS) rocket’s core stage and its four RS-25 engines for a second hot fire test.

After the first SLS core stage hot fire test on Jan. 16 at NASA’s Stennis Space Center near Bay St. Louis, Mississippi, the team put the stand and core stage in a configuration so that the stage and stand could be refurbished. This involved installing platforms on the test stand so that technicians could inspect, access, and perform procedures on the hardware.

The team has now completed this refurbishment work and conducted a review referred to as “the break of configuration review” to transition the core stage hardware to the test configuration for the second hot fire test. During refurbishment, the team thoroughly inspected the stage, dried the four RS-25 engines, and made minor repairs to the engines and thermal protection system.

The team is also modifying and testing the Green Run software for the flight computers based on data from the first hot fire. The team adjusted parameters used by the software logic, which operating on the flight computers automatically monitors a variety of parameters and controls the test during the terminal countdown and after engine ignition. The updated Green Run software was tested in the systems integration test facility at NASA’s Marshall Space Flight Center in Huntsville, Alabama, which has avionics and flight computers identical to the ones in the core stage.

Now, the team is preparing the core stage, the B-2 Test Stand, and the Stennis Test Control Centers for the upcoming hot fire test targeted for the week of Feb. 21. A target date for the test will be announced next week. The core stage is flight hardware that will be used for the Artemis I mission.

This video, the Brains of NASA’s SLS Rocket explains how the SLS avionics system and flight software will work to control the rocket on the Artemis missions. The Green Run test is providing valuable data on how the Green Run test software, which is like the flight software, works with the core stage flight computers to control the rocket.

For updates, please check this blog or the Green Run web site: