After overnight data showed an interruption in helium flow in the SLS interim cryogenic propulsion stage, teams are troubleshooting and preparing for a likely rollback of Artemis II to the VAB at @NASAKennedy. This will almost assuredly impact the March launch window. @NASA will…
— NASA Administrator Jared Isaacman (@NASAAdmin) February 21, 2026
Looks like April now (at best). Also looks like Starship 3 before Artemis II.
[Update a few minutes later]
— Petr Kraus (@PetrKraus42) February 21, 2026
[Afternoon update]
Sorry, second X post fixed now.
UNEXPECTEDLY!!!
The “Update” is the same as the original item.
What we’ve come to expect from NASA. And Boeing.
Jealous of all the attention being lavished on Boeing for its hydrogen leaks that could be fixed at the pad, ULA sees Boeing and raises with a helium glitch that requires a trip back to the VAB. Incontinence, thy name is SLS.
How could they not? Are they going to go out to the pad and hose the interstage with flex seal? It’s not the shuttle days when they had a rotating back to allow additional access. Unfortunately for NASA, they don’t have a production line with a new rocket already built and being tested. They have to fix this one.
I suspect the leak happened because NASA is still using the same batch of helium they used for the Boeing Starliner mission. They’re going with the low bid and buying the cheap off-brand helium instead of the premium non-leaky helium.
I know, right?
Decades ago now, as I was recovering from an ejection from an F4 I was sentenced to Vandenberg AFB, where in part I was responsible for the helium trailers (tube banks) used to support various launch activities….
That was the cheap stuff, too. Very leaky.
You think they’d add some neon, argon, krypton, and xenon so the gas would have a range of fatter atoms that would wedge into any holes that were slightly larger than a helium atom. But maybe such plugs always pop back out because the plug won’t firmly stick to the walls of the hole.
Anyway, I do wonder if the ULA ICPS (with Boeing’s involvement) and the Boeing Starliner share some common sources for the helium lines, valves, and other equipment, or the same engineering team for them.
Dang. Awesome. Seriously.