The Artemis team has had time to review data collected from a successful fourth attempt of a final prelaunch test conducted Monday and determined that no more wet dress rehearsals are needed. The test simulates every stage of launch without the rocket leaving the launchpad at Kennedy Space Center in Florida.
“During the wet dress rehearsal activities, we have incrementally added to our knowledge about how the rocket and the ground systems work together, and our teams have become proficient in launch procedures across multiple sites,” Tom Whitmeyer, deputy associate administrator for NASA’s common exploration systems development, said in a statement.
“We have completed the rehearsal phase, and everything we’ve learned will help improve our ability to lift off during the target launch window.”
Monday’s test included loading all four rocket tanks with supercold propellant, going through a full countdown and draining the rocket tanks. A hydrogen leak and other issues that cropped up during the test prevented the team from getting as far with two countdowns as planned.
Nevertheless, the team concluded that the test attempts have achieved almost all of the objectives needed before launch.
“We only had 13 of the 128 commanded functions that we planned in terminal count that didn’t get successfully accomplished,” Phil Weber, senior technical integration manager for NASA’s Exploration Ground Systems Program, said during a Friday news conference.
“And we looked through those in detail, and it turns out the majority of those have already been validated in prior tests.”
Later Friday, engineers will conduct a test of the booster hydraulic power unit while the rocket still sits on the launchpad, a component that wasn’t included in Monday’s test.
“The units contain hydrazine powered turbines attached to pumps that provide pressure to pivot the booster nozzles used for steering the rocket during ascent,” according to a NASA statement.
Friday evening’s test isn’t required, but engineers want to do a quick spin through the system to mitigate any risk of malfunctions in the future, said John Blevins, chief engineer for NASA’s Space Launch System Program.
Next week, the Artemis team will roll the 322-foot-tall (98-meter-tall) Space Launch System and Orion spacecraft stack back into the Vehicle Assembly Building. The stack will remain in the building for six to eight weeks for repairs and launch preparations.
Engineers have developed a plan to complete final objectives, such as replacing a seal to address the liquid hydrogen leak during that time. The team will also test and install pyrotechnics for the flight termination system hardware, said Cliff Lanham, senior vehicle operations manager for NASA’s Exploration Ground Systems Program.
The uncrewed Artemis I will launch on a mission that goes beyond the moon and returns to Earth. This mission will kick off NASA’s Artemis program, which is expected to return humans to the moon and land the first woman and first person of color on the lunar surface by 2025.
“The team continues to impress me with their creative thinking and resourcefulness,” said Charlie Blackwell-Thompson, Artemis launch director at Kennedy. “Our Artemis launch team has worked quickly to adapt to the dynamics of propellant loading operations. With each milestone and each test, we are another step closer to launch.”