Petro SpaceCom
Janet Petro, director of the Kennedy Space Center, discussed in a Jan. 12 speech major milestones for the center that include both the SLS wet dress rehearsal and first launch in the first quarter of 2022. Credit: SpaceNews/Jeff Foust

ORLANDO, Fla. — NASA officials are holding out hope that the first Space Launch System launch can still take place as soon as March despite a delay in the rollout of the vehicle for a key test until mid-February.

In an update on preparations for the Artemis 1 mission published Jan. 5, NASA said it expected to roll out the SLS to Launch Complex 39B in mid-February for a fueling test and practice countdown called a wet dress rehearsal. After that test, the SLS will go back to the Vehicle Assembly Building (VAB) for final preparations before returning to the pad for the launch.

NASA had earlier planned to conduct that wet dress rehearsal this month. However, the agency said Dec. 17 it delayed the rollout because of a problem with an engine controller, a computer system that operates one of the four RS-25 engines in the SLS core stage. Managers decided to replace the engine controller, a process that delayed the rollout and ruled out a launch in a two-week window in February that NASA had announced in October.

In December NASA said it was “reviewing launch opportunities in March and April” for Artemis 1. “NASA will set a target launch date after a successful wet dress rehearsal test,” the agency said in the Jan. 5 update.

Despite a slip in the rollout to mid-February, agency leadership says a launch in March remains feasible. “Hopefully, we’re going to be completing all of the testing to be able to roll out for a wet dress rehearsal in February and then, hopefully, a launch in March,” NASA Associate Administrator Bob Cabana said in a talk Jan. 11 at the SpaceCom conference here. “That might be tight.”

“We’re going to be looking at a wet dress rehearsal some time next month,” Janet Petro, director of the Kennedy Space Center, said in a separate talk at SpaceCom Jan. 12. She did not offer a date for the Artemis 1 launch, but a slide she presented of major KSC missions in 2022 showed both the wet dress rehearsal and the Artemis 1 launch taking place in the first quarter of the year.

“We’re on the home stretch,” Jeremy Parsons, deputy director of Exploration Ground Systems at KSC, said in a panel discussion at the conference Jan. 11. He estimated about three weeks of integrated testing remaining on the vehicle in the VAB before it is ready to roll out. “We’re going to roll out in mid-February for wet dress rehearsal and launch will probably be about a month or so after that.”

He said that workers replaced the malfunctioning engine controller on the SLS, with the new unit powered up and working normally. Engineers are testing the faulty unit and have replicated the problem in the lab, but are still investigating to find the root cause of the problem. That investigation doesn’t need to be completed before the rollout or the wet dress rehearsal, he later said.

A March launch would need to take place between March 12 and 27, agency officials said in October, a window constrained by the performance of the SLS’s upper stage and a requirement to have splashdown during daylight hours. The next launch window would be between April 8 and 23.

Despite the optimism of NASA officials, some in industry are skeptical that a March launch is feasible. They point to the series of delays in earlier phases of preparations for the mission, making it likely that issues will come up during the wet dress rehearsal that will delay the launch to April or even later in the year.

Agency officials acknowledge they are likely to encounter problems as they go through launch preparations for the first time. “I know we’re going to learn more when we roll out to the pad,” Cabana said. “With that, it’s going to be absolutely awesome next month when we see the rocket roll out to the pad.”

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...