NASA continues to fix issues uncovered during a fueling test of the SLS rocket, which is set to launch a crew of four on a trip around the moon. Engineers are investigating a hydrogen leak that cut short a fueling test last week, delaying the moon mission by at least a month.
During a test known as the wet dress rehearsal last week, NASA discovered a leak of the super-chilled liquid hydrogen that fuels the rocket. The leak prompted launch managers to abort the test.
The wet dress rehearsal is a practice run of the hours leading up to launch, including fueling the rocket and testing key systems during a simulated countdown.
During the previous test on Feb. 2, a leak was detected in an area known as the tail service mast umbilical – which connects the rocket with its launch pad to pump propellant and connect electrical lines to the rocket before its launch. Just ahead of liftoff, mechanisms allow those connections to disconnect instantaneously for a safe launch.
That's where engineers are searching for clues into the leak. They removed two seals near the observed leak, sending them for further analysis and replacing them with new ones. Engineers are reviewing options to test the seals ahead of the next wet dress rehersal. At NASA's Stennis Space Center in Mississippi, NASA is doing additional tests on the connection plates to learn what's happening.
NASA is also determining ways to test the repair work.
That next test is critical – and required – before launch managers give the go-ahead to launch the Artemis II crew, which will send three U.S. astronauts and one from Canada on a trip around the moon and back in the Orion space capsule.
NASA has not announced a planned date for a second wet dress rehearsal. However, the agency said it is changing the test – it's removing a portion that included closing the hatch of the Orion capsule during the countdown. The test will include additional pauses during the countdown, adding an additional hour of testing.
The next launch opportunity opens on March 6, although NASA will not set a target launch date until the completion of a successful wet dress rehearsal.
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