Axiom set to launch Friday, NASA’s new SLS moon rocket to wait for finish of wet dress rehearsal

SpaceX’s Crew Dragon and Falcon 9 rocket are pictured being rolled to the pad ahead of Friday’s planned launch for the Axiom-1 private mission to the International Space Station. Photo by SpaceX/Twitter

“In terms of what day that is, we still have to finish sharpening our pencils,” Free said.

Multiple delays have affected both the SLS wet dress and the Axiom-1 mission, with Axiom-1 now slated to launch from Pad 39A at NASA’s Kennedy Space Center in Florida at 11:17 a.m. EDT on Friday, April 8.

A SpaceX Falcon 9 rocket and Crew Dragon capsule rolled out of the hangar and to the launch pad on Tuesday, ahead of Friday’s launch attempt. From here, crews will prepare the rocket for launch, which includes test firing its engines sometime on Wednesday.

During the test, which is known as a static fire test, the rocket will be held down on the launch pad, and all nine of its Merlin 1D engines will briefly ignite. Teams will then look at the data collected and determine if the rocket is ready to fly.

If all goes as planned, the Falcon 9 will carry four private citizens — Michael López-Alegría, a retired NASA astronaut; Larry Connor, a real estate and technology entrepreneur; Mark Pathy, a Canadian businessman; and Eytan Stibbe, an Israeli entrepreneur and former fighter jet pilot — on a 10 day mission to the ISS.

Typically, SpaceX ferries professional astronauts to and from the orbital outpost for NASA and its space station partners. However, this flight marks the first time that four citizens will fly to the station to do research and other investigations.

Twice delayed for SLS test

There’s been some uncertainty around the launch date, as NASA is also trying to complete a wet dress rehearsal of its next moon rocket, the SLS, on an adjacent launch pad.

The agency had planned to put its newest megalauncher through its paces, simulating the procedures teams would carry out on the actual day of launch.

That test was scheduled to take place over the weekend, culminating in fueling the rocket with liquid hydrogen and oxygen.

The test was pushed back and it ultimately ended early due to a valve issue. Because of the unexpected anomaly, engineers decided to put SLS testing on hold for now, in favor of launching the Axiom-1 mission.

According to NASA’s Artemis 1 launch director, Charlie Blackwell-Thompson, despite ending prematurely, the test completed many of its objectives, with the open items relating to cryogenics or fuel loading.

“Wet dress is all about cryogenics, but it is also about day of launch configurations and countdowns,” she said during a news teleconference about the status of the testing. “So there were a significant amount of test objectives that were completed.”

Blackwell-Thompson went on to say that the team was able to load 50% of the vehicle’s liquid oxygen supply onto the rocket before they ran into a test-ending valve issue.

One of the valves on the liquid hydrogen system was stuck in the closed position when it should have been open, preventing the teams from fueling the rocket further.

She also confirmed that the wet dress rehearsal could pick up where it left off and the teams could resume the countdown whenever the rocket and the range are ready. Right now, however, no future date has been set.

Instead the range will turn its attention to the Axiom-1 mission.

In regards to when SLS might launch, the team says that June is still a possibility, depending on how the rest of the testing goes.