NASA is working through a technical issue affecting the Artemis II rocket at Kennedy Space Center in Florida, where the Space Launch System and Orion spacecraft remain on the launch pad at Complex 39B. Engineers observed an interruption in the flow of helium to the interim cryogenic propulsion stage late on 21 February and began reviewing data overnight. The agency is preparing for a possible rollback of the rocket and spacecraft to the Vehicle Assembly Building while teams assess the fault. Helium is used to maintain environmental conditions for the upper-stage engine and to pressurise its propellant tanks. The rocket remains in a safe configuration as engineers consider repair options at the pad or inside the assembly building. Weather conditions are also shaping the immediate schedule.
NASA engineers are troubleshooting a helium issue on Artemis II under review at Kennedy Space Center
The issue centres on the upper stage of the Space Launch System, part of NASA’s Artemis II mission. During operations after the recent wet dress rehearsal, teams were unable to properly flow helium through the system. The rehearsal itself concluded on 19 February and the systems functioned as expected at the time.Engineers are examining several possible causes. Attention is on the interface between ground and rocket lines, a valve within the upper stage, and a filter positioned between ground equipment and the rocket. Data from Artemis I is also being reviewed, as that mission required troubleshooting linked to helium pressurisation before launch.
Rollback preparations could affect March launch window
Teams are preparing to remove pad access platforms installed earlier this week. These platforms cannot be taken down in high winds, and stronger weather is forecast. Preparations now are intended to keep options open.A rollback to the Vehicle Assembly Building at Kennedy Space Center would rule out a launch in March. However, NASA says early planning may help preserve a possible April launch window, depending on findings and repair timelines. For now, the rocket stands at the pad while engineers work through the details.
