NASA cleared a milestone in preparation for Green Run testing of its Space Launch System (SLS) core stage with an Aug. 23/24 lift and installation of the core stage pathfinder simulator onto the B-2 Test Stand at Stennis Space Center near Bay St. Louis, Miss. The lift and installation of the core stage pathfinder – a size and weight replica of the SLS core stage – is helping teams at Stennis prepare for the Green Run test series. For this test of the new core stage, Stennis will lift the flight core stage for Artemis 1, the first SLS mission into the stand. SLS and the new Orion spacecraft being built are the foundation for NASA’s Artemis Program, which will send the first woman and next man to walk on the Moon by 2024.
Stennis modified the B-2 Test Stand for the core stage Green Run testing. The procedure involved lifting the core stage pathfinder from its horizontal position on the B-2 Test Stand tarmac with the facility boom crane line attached to the forward end and a ground crane line attached to the aft end. The pathfinder then was “broken over” into a vertical position. Once the ground crane line was disconnected, the core stage pathfinder was lifted into place by the stand boom crane. This “fit test” validated auxiliary lift equipment, procedures, and verified that stand modifications and preparations are in place and prepared for delivery and testing of the SLS core stage flight hardware.
To prepare for the test, Stennis modified or upgraded every major area and system of the test stand, as well as the high-pressure industrial water system and high-pressure gas facility that support test operations. NASA is building the SLS flight core stage at its Michoud Assembly Facility in New Orleans and is scheduled for transport to Stennis by the end of the year. The stage recently completed a critical review in preparation for adding the last piece of the core stage structure: the engine section. After this piece is added, the four RS-25 engines can be connected to the stage. When the stage is completely assembled, NASA’s Pegasus barge will deliver it to Stennis. For the Green Run test, the core stage flight unit will be lifted and installed onto the B-2 stand, using procedures developed and practiced during the recent core stage pathfinder lift. NASA then will conduct a series of tests to check out stage systems and make sure all are working as needed. Once systems are checked, NASA will conduct a full hot fire test of the stage, firing its four RS-25 engines simultaneously, just as during an actual launch. The hot fire test will generate more than 2 million pounds of combined thrust and provide critical performance data needed to demonstrate the core stage design is flightworthy and ready for launch. Following necessary refurbishment of the stage, it will be transported by barge to Kennedy Space Center in Florida. At Kennedy, the stage will be mated with other SLS major elements and prepared for launch of the Artemis 1 mission.
