Washington, May 30 (IANS): After halting Artemis 1 moon rocket's "wet dress rehearsal" several times, NASA now targets to attempt the crucial fuelling test of its Space Launch System (SLS) megarocket on June 19.
NASA officials announced plans to start rolling the Artemis 1 out from the huge Vehicle Assembly Building (VAB) at NASA's Kennedy Space Center (KSC) in Florida to Launch Pad 39B at around midnight EDT (0400 GMT) on June 6, Space.com reported.
They expect to begin the roughly 48-hour wet dress on June 19, the report said.
The Artemis 1 stack -- a huge SLS rocket with an Orion crew capsule on top -- first rolled out to Pad 39B in mid-March.
Although the wet dress began on April 1 and was supposed to wrap up two days later, the team encountered several problems, including a stuck valve on the mission's mobile launch tower and a hydrogen leak in one of the "umbilical" lines connecting the tower to the SLS. This led to delay and ultimately a halt after three fuelling attempts.
On April 25, team members rolled the Artemis 1 stack off Pad 39B back to KSC's cavernous VAB to investigate the problems and make the necessary fixes.
NASA officials outlined several of these fixes. For the leaky umbilical, for example, it was found that flange bolts had inadvertently loosened, compromising their seal, the report said.
"Those seals age with time," John Blevins, chief engineer for the SLS programme at NASA's Marshall Space Flight Center in Alabama, was quoted as saying.
"We had tightened those down previously, and we hadn't done a torque checks over the period of time that we've found now that those seals age," he added. Blevins expressed confidence in the repair work, saying that Artemis 1 team members have taken steps to prevent leakage.
A helium check valve and related hardware were replaced on the SLS' upper stage, which is called the Interim Cryogenic Propulsion Stage (ICPS).
Modifications were also made to the ICPS umbilical boots, which are involved in the quick disconnect between SLS and the mobile launch tower during liftoff. Additional leak detectors were also added to components of the system responsible for handling liquid hydrogen, NASA officials said.
Artemis 1, was earlier scheduled to launch in late May 2022. Now, NASA plans to set the stage for its first launch in August, provided the wet dress rehearsal succeeds this time.