NASA has announced it plans to perform the first hot fire test of an SLS core stage on January 16. The stage is expected to be utilised for Artemis 1, the maiden uncrewed mission of NASA’s push to return to the Moon.
The first SLS core stage has been undergoing Green Run tests on the B-2 Test Stand at NASA’s Stennis Space Center since January 2020. The eight-part test campaign is designed to put every element of the rocket stage, and the procedures NASA will perform when preparing the stage for flight, through their paces and culminates in the hot fire test.
This final stage of the Green Run test campaign will see all four of the stage’s RS-25 engines ignited for a full eight-minute burn. The burn is designed to simulate the exact performance the stage would be expected to achieve during flight.
Once the test is completed, the SLS core stage will be removed from the B-2 Test Stand, refurbished at Stennis, and then placed on NASA’s Pegasus barge for its trip to the Kennedy Space Center. It will then be mated with its upper stage, boosters, and an Orion spacecraft in preparation for Artemis 1, the maiden flight of the SLS launch vehicle, and the first mission of the agency’s Artemis program.
In addition to announcing the date for the upcoming hot fire test, NASA also revealed the details behind the abrupt conclusion of the December 20 wet dress rehearsal.
This phase of the Green Runs tests marked the first time cryogenic liquid propellant was fully loaded and then drained from the SLS core stage’s two tanks. Although the test initially went as planned, it was automatically stopped several minutes early due to the premature closure of a valve.
A subsequent investigation of the incident concluded that the predicated closure of the valve was off by a fraction of a second. Engineers have since corrected the timing issue enabling teams to continue with the final Green Run test.