NASA will televise a test Wednesday to confirm whether a repair to its Space Launch System (SLS) rocket fixed the hydrogen leak that forced officials to scrub an earlier launch attempt.
The super-heavy launch vehicle has yet to leave the launch pad at Kennedy Space Center in Florida since it first rolled out last month. The plan is to fly the SLS to the Moon so its empty Orion capsule can orbit the natural satellite before returning to Earth. The US space agency eventually plans to use SLS to send humans — the first woman and another man — to the moon with these astronauts on the Orion pod as part of the Artemis program later this decade.
NASA has now attempted to send the rocket into space twice, but engineers have encountered problems each time trying to load the multi-billion dollar rocket with propellant. Hence all the attention to it now.
Liquid hydrogen is an effective light fuel when burned with oxygen, but it’s a delicate substance to handle. It must be pressurized and stored at cryogenic temperatures and has a tendency to leak. NASA has since removed and replaced seals to plug a leak at a quick-disconnect point where the fuel is pumped to the rocket’s base. It is this leak that forced it to abort its last launch attempt on September 3rd.
Before NASA makes one third try For launch, it will conduct a final check on September 21 during a to see if hydrogen fuel is still leaking from the vehicle streamed live Event beginning at 0715 EDT (1115 UTC).
“The demonstration test will allow teams to validate the repair of a hydrogen leak detected during an Artemis I launch attempt in early September, evaluate and perform updated propellant loading procedures additional evaluations“, the space agency said in an opinion. “The demonstration ends when the objectives for the test are met.”
NASA is just weeks away from trying the SLS Moon rocket launch again
The test result will be crucial in determining whether NASA can make a third launch attempt on September 27th. If the repair didn’t fix the problem, officials will delay the launch until the next launch window on October 2.
Mike Sarafin, the Artemis mission manager, said there was a slim chance Wednesday’s lightning could force them to postpone the test. Weather permitting, engineers will carefully refuel the rocket to minimize the risk of a pressure and temperature spike, he explained in a briefing on Monday. NASA experts will measure hydrogen levels in specific confined areas of the rocket to detect leaks.
“Ideally, we want to keep it under four percent,” said Jeremy Parsons, deputy manager of the Exploration Ground Systems program at NASA’s Kennedy Space Center, when discussing the maximum amount of gas NASA was willing to vent. “The reason the four percent is set is the flammability of hydrogen in air. It’s really a relatively conservative limit, other than that we put it there because you want to keep that all under control.”
When the previous attempt was scrubbed, officials had detected eight percent – double the accepted limit – of hydrogen seeping into components inside the launch vehicle.
The SLS has never been flown into space before. A successful launch will allow NASA to test its rocket and Orion capsule for the first time. The capsule will be placed in orbit around the moon for a little over a month before returning to our homeworld. Orion is not expected to take astronauts to the moon until 2025 at the earliest. ®
https://www.theregister.com/2022/09/20/nasa_sls_test/ NASA tests Artemis SLS rocket fuel leak repairs this week • The Register