The fourth attempt at testing began before the final launch on Saturday and the missile tanks filled up on Monday.
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 the ultra-cooled thrusters, running a complete countdown simulating 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 women and men on the moon by 2025.
Three previous test attempts in April were unsuccessful, and ended before the missile could be fully loaded with fuel due to multiple leaks. NASA says these bugs have now been fixed.
A NASA team rolls a 322-foot (98-meter) stack of Artemis I rockets, including the Space Launch System and the Orion spacecraft, to the launch pad at Kennedy Space Center in Florida on June 6.
wet test steps
The experiment began at 5 p.m. ET on Saturday with a “call for seasons” — when all teams associated with the mission arrive at their consoles and report they are ready to begin testing and a two-day countdown begins.
Preparations over the weekend made the Artemis team begin loading the rocket into the rocket’s core and upper stages on Monday morning.
The tanks were suspended Monday morning due to a specific problem with the backup supply of nitrogen gas. The release team replaced the valve that was causing the problem. To ensure that the backup source is working as expected, it has been replaced as the primary test source.
The comment was captured 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 center stage before moving to the rocket’s upper stage. The hatch was visible from the missile throughout the operation.
The base stage was almost completely full and the team was filling up the upper stage when several problems occurred after 2:00 PM ET.
The team detected a hydrogen leak in a rapid separation line in the central stage. Their first choice did not work and they studied Options to close the leak.
Something from the glow pile, where excess liquid hydrogen from the rocket is being burned with a propane flame, caused a small fire in the grass toward a dirt road. The team monitored the grass fires and expected them to break out as soon as they reached the dirt road.
The test exceeded the scheduled 30-minute waiting period, which was extended as engineers tried to work on solutions to the hydrogen leak.
The Artemis team has decided to go ahead with the countdown, while concealing the hydrogen leak problem, “to move forward with testing our wetsuit today,” according to a tweet from NASA’s Earth Exploration Systems.
The 10-minute countdown began at 7:28 p.m.
There is usually downward aggression during exercise. First, team members typically go through a 33-second countdown before launch and then break the cycle. The clock is reset and then the countdown begins again and lasts until approximately nine seconds before the launch begins.
Monday’s short countdown ended prematurely with 29 seconds left on the countdown clock. Computer science of the SLS missile led to a hack, but the exact science has not been shared. Before the countdown, the team said that if the computers involved in the countdown detect a hydrogen leak, it could be similar to a check engine light forcing the countdown to stop early.
Once the countdown stopped, the Artemis team worked to ensure the safety of the vehicle.
“It’s definitely a good day for us,” said Charlie Blackwell Thompson, Artemis launch manager for NASA’s Earth Exploration Systems Program, after achieving several specific milestones in the wet cloth goals, such as putting the entire rocket into a tank and passing the countdown.
The next steps, she said, would be to evaluate all the data collected from the test, including problems, and develop a plan moving forward.
Blackwell-Thompson said previous attempts at wet cloth training had already accomplished many goals to prepare the missile for launch.
There is a long history behind extensive testing of new systems before launch, and the Artemis team faces similar experiences as the Apollo and Space Shuttle teams, including multiple test attempts and delays.
