NASA completes second Artemis 2 fueling test

WASHINGTON — NASA completed a second wet dress rehearsal for the Artemis 2 mission on Feb. 19 without any of the hydrogen leaks seen in the first such test earlier this month.

NASA declared the wet dress rehearsal, or WDR, complete at 10:16 p.m. Eastern. During the test, NASA loaded the Space Launch System core and upper stages with liquid hydrogen and liquid oxygen propellants, then conducted a practice countdown. That included one countdown that stopped at T-minus 33 seconds, as planned, then recycled for another terminal countdown that stopped at T-minus 29 seconds.

The test appeared to avoid the problems seen during the first WDR on Feb. 2, when the agency reported liquid hydrogen leaks while fueling the core stage and later while pressurizing the core stage tanks during the terminal countdown. The agency decided to replace and test seals at the interface between ground equipment and the SLS.

NASA reported no leaks during fueling or subsequent countdown operations. The agency said there were only minor issues during the WDR, including a ground communications issue in the launch control center and a “voltage anomaly” in a booster avionics system that briefly paused the countdown.

“Hydrogen gas concentrations remained under allowable limits, giving engineers confidence in new seals installed in an interface used to route fuel to the rocket,” NASA said in a statement after completing the WDR.

The agency will hold a briefing Feb. 20 to discuss the results. NASA has not set a launch date for Artemis 2, and agency officials said they will complete their review of data from the WDR before doing so.

However, NASA said in its statement that the four-person Artemis 2 crew would enter prelaunch quarantine on Feb. 20. That quarantine typically begins about two weeks before launch, and starting it on that date “preserves flexibility in the March launch window,” the agency said.

That window runs from March 6 to 11, with two-hour launch windows opening on the evenings of March 6, 7, 8 and 9 and shortly after midnight on March 11.

Preparations for Artemis 2, the first crewed flight of the SLS and Orion spacecraft, are facing additional scrutiny after NASA released a report Feb. 19 assessing the technical and organizational failures of Boeing’s CST-100 Starliner crewed test flight in 2024. Boeing is also the prime contractor for the SLS.

At a news conference about the report, NASA Administrator Jared Isaacman downplayed any connection between the two programs, citing differences in technologies and contracting approaches.

“SLS leverages a lot of components that go back to the Space Shuttle program, procured and assembled in a more traditional way,” he said, along with “the mindset that this is now the most important human spaceflight mission in more than a half century.”

“There cannot be enough eyes on this program. I’ve dispatched second and third and fourth sets of eyes during the Artemis 2 campaign,” he said. “We are putting a lot of attention on this because this is a mission we do not want to get wrong.”