Artemis launch live updates: NASA plan aims to fix hydrogen leak

Follow our live Artemis I launch updates from Kennedy Space Center. Latest updates below: The $4.1 billion moonshot is slated to lift off from KSC’s Launch Pad 39-B during a two-hour window that opens at 2:17 p.m. The Space Launch System rocket looks to become the most powerful rocket to ever launch from Earth using 8.8 million pounds of thrust to propel the Orion spacecraft on its way to a 37-day mission to orbit the moon several times before heading back to splash down in the Pacific Ocean on Oct. 11 coming in faster than any previous human-rated spacecraft traveling 24,500 mph producing re-entry temperatures of near 5,000 degrees Fahrenheit.

After evidence of continued leaking on the liquid hydrogen (LH2) tanking, engineers have been approved by the launch director to stop the flow of the LH2, close the vehicle fill-in drain valve to protect the rocket, and then bring up pressure on the ground transfer line with helium in an attempt to “re-seat” a quick disconnect from the supply side that connects to the SLS rocket.

“This is the plan that they have in place to try and stop a leak which they have seen some indication that it continues to leak when they raise the pressure on the liquid hydrogen, said said Derriol Nail,” with NASA communications during live commentary.

As of 8:45, the LH2 tanking, which was being done manually, was at 43,500 gallons, or 8%, of the 537,000 gallons while liquid oxygen (LOX) was at more than 111,000 gallons, or 57% of its 196,000 gallons.

Richard Tribou

NASA resumed liquid hydrogen (LH2) tanking at 7:50 a.m., but manually, but as of 8:05 a.m. the tanks had about 10,000 gallons, or 2% of the 537,000 gallons while liquid oxygen (LOX) was at more than 64,000 gallons, or 33% of its 196,000 gallons.

By 8:15, LOX was up to 40% with LH2 up to 4%. NASA engineers reporting that the slow fill of LH2 is going well, but they will continue with manual flow for “a while.”

The LOX load had been slowed as teams worked the LH2 issues because the LOX capacity cannot surpass 50% unless there’s at least 5% of the LH2 in the tank. Full speed flow of the LOX though resumed by 8:15.

The delay in taking has put off some other items planned in the countdown including a planned test at 8 a.m. for the bleed system, the flow of liquid hydrogen to cool the four RS-25 engines at the base of the core stage that is required before liftoff. That test was among issues that forced NASA to scrub Monday’s attempt, but ended up being blamed on a faulty sensor that showed that one of the four engines was not approaching the minus 420 degrees Fahrenheit target. After data analysis, NASA managers determined that all four engines had reached sufficient cooling, and the sensors had been wrong.

Richard Tribou

A new leak has been detected in the engine cavity during liquid hydrogen tanking in the Space Launch System core stage. Teams are troubleshooting by warming up the area, NASA said. It’s the second time NASA has halted LH2 tanking this morning, while also having had to halt the liquid oxygen tanking for a short time.

The halt will take about 30 minutes, which will slow the timeline, with the team updating the launch director with a plan forward. The leak is in something called the plate cavity, which suggests NASA said it is coming from one of the quick disconnect lines, which have proven to be prone to leaks in both the wet dress rehearsals in April and June and last Monday’s launch attempt.

Liquid oxygen loading is still in flow, although a little slower, at 15% full with about 30,000 of the 196,000 gallons needed to fill the tank. NASA has a rule that LOX loading cannot exceed 50% full unless the liquid hydrogen has at least 5% capacity filled.

Richard Tribou

The countdown clock came out from its pre-planned 2 1/2-hour hold at 7:07 a.m. Its next planned hold, a 30-minute hold, is slated to occur when the clock gets to T-10.

Richard Tribou

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With darkened skies during thunderstorms at launch pad 39-B, Artemis 1 sits ready for lift-off at Kennedy Space Center, Fla., Friday, September 2, 2022. NASA will make a second attempt to launch the moon-orbit test flight at 2:17pm on Saturday. (Joe Burbank/Orlando Sentinel) (Joe Burbank/Orlando Sentinel)

Both the liquid hydrogen and liquid oxygen flows to the core stage of the Space Launch System have resumed after both experienced some pressure issues.

For the LOX, they’ve got the pump repressurized and stable.

“Minimal impact to the timeline. No impact to the flow rate going forward,” said Nail.

And then the LH2 slow fill was given the OK to start again.

Richard Tribou

Both the liquid hydrogen and liquid oxygen flows to the core stage of the Space Launch System were halted after each experienced some pressure issues.

The liquid hydrogen loading halted when there was an over-pressure warning on a vent line, that caused it to stop flow automatically.

There was no damage to the hardware, said Nail.

“They’re currently working a manual configuration to get the vent line going again,” he said.

On the liquid oxygen side, he said, “They had chilled down the lines, they were in drain back, there was a pressure measurement reading as well and so they backed off the pumps for the moment, but looking to reactivate those pumps here shortly.”

Richard Tribou

Officials in Brevard County are expecting perhaps twice as many people for today’s planned Artemis I launch than for Monday’s first attempt.

Brevard County’s Emergency Operations Center is predicting between 200,000 and 400,000 people will come to the Space Coast to witness the historic moon launch. Monday’s crowd estimate was between 100,000 to 200,000.

Why so many more people for Artemis’ second attempt? It’s because of the long Labor Day weekend.

“Hotels are already full …There’s no school, and fewer people are going to work. It’s possible we will see double what we might have anticipated for the first launch,” said Don Walker, an emergency manager of Brevard County.

The Florida Highway Patrol and Brevard County Sheriff’s Office will be out coordinating with Brevard’s EOC trying to keep traffic flowing, but congestion will happen, Walker said.

“Brevard is 72 miles long and 20 miles wide, there are only a few ways to travel out,” he said. “We understand it’s a historic moment. We’re lucky we can have this happen here for everyone to witness. If you’re living here, we suggest watching from your driveway, but if you’re heading out, anticipate long delays.”

Joe Mario Petersen

After several delays in tanking on Monday, NASA decided to adjust the timeline for filling the 733,000 combined gallons of both liquid oxygen and hydrogen into the core stage. Part of that was an earlier flow of the liquid hydrogen into the tank.

The breakdown is 537,000 gallons of liquid hydrogen kept at minus 423 degrees Fahrenheit while liquid oxygen is kept at minus 297 degrees Fahrenheit.

The countdown clock is amid a pre-planned 2 1/2-hour hold at T-6 hours, 40 minutes. The clock will resume at 7:07 a.m.

“Launch team discussing a couple of issues,” said Derriol Nail, with NASA communications during live commentary that began this morning at NASA.gov/live.

NASA is avoiding the weather headaches it saw the first time it tried to load the Space Launch System from cryogenic fuel on Monday as the risk of lightning is only 10% for the start of tanking of super-chilled liquid oxygen and liquid hydrogen.

Lightning risk above 20% would have halted the start of tanking, like it did on Monday for nearly an hour, part of NASA’s hurdles that eventually led teams to scrub.

For today’s leadup to launch though, Artemis launch director Charlie Blackwell-Thompson gave the “go” for tanking at 5:36 a.m. after a weather briefing with Space Launch Delta 45′s weather officer Mark Burger.

“He said we are green on weather for tanking,” said Nail, with NASA communications during live commentary that began this morning at NASA.gov/live.

The teams have been given the go to begin loading of the liquid oxygen, which will start with a slow fill before switching to fast fill. That flows into the upper part of the core stage, and then the larger lower part of the core stage will begin slow fill of liquid hydrogen. The new timeline, though, has liquid hydrogen flow starting earlier to give teams more time to deal with problems that might arise, as it did on Monday.

See the timeline for tanking and other operations leading up to the beginning of the two-hour launch window at 2:17 p.m.

Richard Tribou

For Artemis I, NASA officials are hopeful the second time is the charm as they attempt to launch the massive rocket to the moon this afternoon at Kennedy Space Center’s launchpad 39-B. The two-hour launch window opens at 2:17 p.m. today.

After an issue with one of the rocket’s engines caused a scrub of Monday’s planned launch, NASA engineers spent a lot of time going over data gathered during the countdown.

They found that inaccurate sensor readings in the troublesome Artemis engine was to blame for the scrub. Although there were several issues during the countdown that caused stress on the launch teams, the false reading was that one of the four RS-25 engines at the base of the Space Launch System rocket core stage had not cooled enough for a safe launch.

Roger Simmons

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