The fourth attempt for the final pre-launch test began on Saturday, and refueling of the rocket is expected to begin on Monday morning.
The critical test, known as wet wear training, simulates each stage of the launch without the rocket leaving the launch pad at the Kennedy Space Center in Florida.
This process includes loading ultra-cooled propellants, performing a complete countdown simulating a launch, resetting the countdown clock, and draining the missile tanks.
The results of training in wet clothes will determine when Artemis I will embark on a mission beyond the Moon and back to Earth. This mission will launch NASA’s Artemis program, which is expected to return humans to the moon and land the first woman and first people of color on the moon by 2025.
Three previous attempts at rehearsal in April were unsuccessful, and ended before the missile could be fully loaded with fuel due to various leaks. NASA says these errors have since been corrected.
The NASA team rolls a 322-foot (98 m) stack of Artemis I rockets, including the Space Launch System and Orion spacecraft, to the launch pad at Kennedy Space Center in Florida on June 6.
Wet rehearsal steps
The rehearsal began at 5 p.m. ET on Saturday with a “Call to Stations” — when all teams associated with the mission arrive at their consoles and report that they are ready to begin testing and a two-day countdown begins.
Preparations over the weekend will see the Artemis team begin loading propellant into the rocket’s core and upper stages.
The tanks were suspended Monday morning due to an identified problem with the backup supply of gaseous nitrogen. The launch team replaced the valve that was causing the problem. In order to ensure that the backup supply works as expected, it has been replaced as the primary supply for today’s test.
The comment was lifted at 9:28 a.m. ET. Liquid oxygen, cooled to minus 297 degrees Fahrenheit (minus 182 degrees Celsius), and liquid hydrogen were used to fill the core stage before moving to the upper stage of the rocket. The vent was visible from the missile throughout the operation.
The base stage was mostly filled and the team was filling the upper stage when several issues occurred after 2pm ET.
The team has detected a hydrogen leak in a rapid core phase separation line and are repairing it. Their first choice didn’t work and they are looking to see if there is another way to close the leak.
Something from the glow pile, where excess liquid hydrogen from the rocket we’re burning with a propane flame, is causing a small fire in the grass toward a dirt road. The team monitors grass fires and doesn’t expect it to become a problem because it will likely put out the fire when it reaches the dirt road.
Currently, four tanks of the missile are full.
The test has exceeded the planned 30-minute waiting period, which has been extended while engineers try to work on solutions to the hydrogen leak.
If the leak cannot be closed today, the Artemis team may go through a planned countdown and see how far they can get.
There are two countdowns during wet clothes rehearsal. First, team members It will count down to 33 seconds before launch, then stop the cycle. The clock will be reset; Then the countdown will resume again and last until about 10 seconds before the launch occurs.
According to an update on the NASA website, “During testing, the team may maintain the countdown as necessary to check conditions before resuming the countdown, or extend beyond the test window, if necessary and resources permit.”
Previous attempts at wet-weather training have already completed many goals to prepare the rocket for launch, Charlie Blackwell-Thompson, Artemis launch manager for NASA’s Earth Exploration Systems Program, said during a press conference Wednesday.
“Hopefully we can finish it this time and finish the cryogenic loadings along with the final count,” she said. “Our team is ready to go, and we look forward to returning to this test.”
Once the Artemis rocket group completes its rehearsal, it will return to the Space Center Vehicle Assembly Building to wait for launch day.
There is a long history behind the grueling testing of new systems before launch, and the Artemis team faces experiences similar to those of the Apollo and shuttle era teams, including multiple test attempts and delays.
“No one on the team abdicates the responsibility that we and our contractors have to manage and deliver, and deliver, the means that meet these flight test objectives for (Artemis I), and meet those of Artemis I,” said Jim Frey, associate director of NASA’s Exploration Systems Development Mission Directorate, During the press conference held last week.