Artemis 2 rocket rolls back to the garage after helium flow interruption

Engineers detected an interrupted helium flow to Artemis 2's interim cryogenic propulsion stage after a wet dress rehearsal, and NASA will roll the SLS and Orion back to the Vehicle Assembly Building for inspection, removing the March launch window from consideration.

NASA is rolling its Artemis 2 Space Launch System rocket and the stacked Orion spacecraft back to the Vehicle Assembly Building at Kennedy Space Center after engineers observed an interruption in helium flow to the rocket's interim cryogenic propulsion stage. The interruption was detected during a wet dress rehearsal that otherwise showed no major issues. Helium helps maintain environmental conditions for the upper stage engine and pressurize the liquid hydrogen and liquid oxygen propellant tanks. Because the affected section cannot be accessed safely on the launchpad, teams will move the vehicle for a closer inspection. Key details: - Engineers observed interrupted helium flow to the interim cryogenic propulsion (upper) stage during monitoring after a wet dress rehearsal. - Helium is used to maintain proper environmental conditions for the stage's engine and to pressurize the liquid hydrogen and liquid oxygen tanks. - NASA will roll the SLS and Orion back to the Vehicle Assembly Building at Kennedy Space Center to allow safe access for troubleshooting and inspection. - Weather permitting, teams planned to begin the rollback on Tuesday; NASA said this development removes the March launch window from consideration. - Engineers are investigating possible causes including a connection point between the rocket and ground equipment, an upper-stage valve, or a filter in the helium line. - Artemis 2 would be the first crewed flight of SLS and Orion and the first crewed mission near the Moon since the Apollo era; Artemis 1 experienced similar lead-up rollbacks for technical issues and weather. Summary: The interrupted helium flow has prompted a rollback and is expected to delay the earliest possible launch beyond March, with April becoming the next tentative target if inspections proceed quickly. Teams will inspect the affected hardware inside the Vehicle Assembly Building and troubleshoot the helium system to identify and repair the fault. Undetermined at this time.