Engineers are troubleshooting a helium flow issue in the Interim Cryogenic Propulsion Stage discovered during final pad processing of Artemis II.
Artemis II is scheduled to fly around the Moon and needs to launch in 2026.
ASAP noted progress in Artemis II readiness.
The rollback of the SLS rocket rules out March launch windows for Artemis II and makes the first week of April the earliest possible launch attempt.
NASA rolled back the Artemis II rocket to the Vehicle Assembly Building for repairs, removing the March launch window from consideration.
NASA plans to roll the Artemis II Moon rocket off the launch pad as soon as Feb. 24, 2026, weather permitting.
A February 2 cryogenic fueling test for Artemis II experienced excessive hydrogen leaks.
The Artemis II rocket would be transferred to facilities at Kennedy Space Center for the rollback and related work.
A failed check valve onboard the vehicle is a potential fault consistent with the Artemis I failure signature, despite corrective actions taken on Artemis II to minimize reoccurrence.
Artemis II will fly four astronauts around the Moon and back.
NASA observed an interrupted flow of helium to the interim cryogenic propulsion stage (ICPS) on the Artemis II Space Launch System on Feb. 21.
NASA is completing technical checks on the helium feed system for the Artemis II rocket’s upper stage before proceeding with further mission activities.
NASA will begin preparations for rollback, which eliminates the March launch window for Artemis II.
Helium is used to pressurize propellant tanks during launch preparations for the Artemis II rocket.
A rollback of the Artemis II rocket from the launch pad would allow in-depth intervention on the affected helium system before resuming operations.
The Artemis II vehicle is in a safe configuration using ground Environmental Control System (ECS) purge for the engines instead of the onboard helium supply.
The decision to roll the Artemis II rocket off the pad is contingent on weather conditions along the transfer route between the pad and the integration facility.
During a routine repressurization operation, the Artemis II team was unable to get helium flow through the vehicle.
Engineers preparing the Artemis II rollout encountered an issue with the flow of helium to the rocket’s upper stage.
Accessing and remediating the identified helium-flow issues on Artemis II can only be performed in the Vehicle Assembly Building.