In continued preparations for the Artemis I wet dress rehearsal test, with tanking targeted for Monday, teams encountered an issue maintaining helium purge pressure on the upper stage engine after change-out of a regulator on the mobile launcher. The RL10 engine on the upper stage uses helium to purge the engine and also to activate upper stage valves during wet dress rehearsal operations. After initial troubleshooting, the team reestablished normal helium purge, and is continuing work to determine the cause of a restriction in the helium flow. Engineers will conduct troubleshooting tomorrow to confirm and characterize system performance. If needed, the mission management team will meet Sunday to disposition any adjustments in the procedures or modifications in test objectives as necessary. After the wet dress rehearsal test, SLS and Orion will return to the Vehicle Assembly Building, and engineers will conduct additional inspections of the related flight systems to further evaluate system performance. The Space Launch System rocket, the Orion spacecraft, and the supporting ground system elements remain in stable condition.
The countdown for the two-day test is currently slated to begin with call to stations beginning at 5 pm EDT on Saturday, April 9 with T-0 planned for 2:40 pm on Monday, April 11. While engineers investigate the issue, teams continue to refine the test schedule to account for insights gained during the previous runs and activities, or test objectives, that were completed earlier this week and no longer need to be included in the next test run, such as configuring ground support equipment. Pending additional analysis, NASA expects to have a forward plan tomorrow for wet dress rehearsal testing.
Check back at this blog for an update on wet dress rehearsal testing for the Artemis I mission. NASA is streaming live video of the rocket and spacecraft on the Kennedy Newsroom YouTube channel. Real-time updates will be provided on the Exploration Ground Systems Twitter account with “go” for tanking.