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NASA aborts fueling in SLS dress rehearsal countdown

UPDATE: Dress rehearsal countdown to resume, now aiming for a 2:40 pm (Eastern) T-0 tomorrow, April 4th.

NASA announced this morning that it has aborted fueling in SLS dress rehearsal countdown because of a problem with the rocket’s mobile launcher.

Teams have decided to scrub tanking operations for the wet dress rehearsal due to loss of ability to pressurize the mobile launcher. The fans are needed to provide positive pressure to the enclosed areas within the mobile launcher and keep out hazardous gases. Technicians are unable to safely proceed with loading the propellants into the rocket’s core stage and interim cryogenic propulsion stage without this capability.

It appears engineers are assessing the issue and hope to resume the countdown so as to proceed with rocket fueling tomorrow.

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  • Patrick Underwood

    NASA arrogantly and needlessly prioritized this test over the private crewed Axiom 1 mission to ISS, bumping it by three days. Now, because problems like today’s could reoccur indefinitely, that flight might be bumped again, possibly by weeks or months, depending on the ISS visiting vehicles schedule.

    Even if it doesn’t happen, it’s a real risk NASA chose to impose on a private company for the sake of a few measly days in the decades-long slow-motion saga of SLS. Truly awful management.

  • Patrick Underwood

    Update, Axiom-1 has been postponed. Don’t know if it’s related to SLS.

  • Skunk Bucket

    Now where did I put my shocked face? I know it’s around here somewhere.

  • Mitch S.

    “The fans are needed”

    No surprise SLS has a lack of fans.
    But as long as it’s fans in Congress stay active, SLS will trundle along.

  • Jeff Wright

    Ground Support Equipment is also holding things up at Boca Chicka as well…as from talk of GSE at SpaceNews commentary section….not just regs.

  • Richard M

    Looks like they’re going to try again tomorrow.

    In the presser, they said they could probably do Tuesday, too, with range conflicts, but after that, it gets sticky.

    NASA arrogantly and needlessly prioritized this test over the private crewed Axiom 1 mission to ISS, bumping it by three days.

    I don’t think it was *unreasonable* to bump Axiom and Crew-4 by a few days, if that is all it comes to. If not…

    One concern that may be at work is that the certification on the SLS solid rocket boosters expires in July. And while it’s more complicated than a magic day when the solids become unusable, it’s clear that the sooner they launxch them, the better. And that may be what is at work in prioritizing the wet dress rehearsal.

  • Jeff Wright reported several lightning strikes…

  • Edward

    Jeff Wright,
    You wrote: “Ground Support Equipment is also holding things up at Boca Chicka as well

    Why would you think that SpaceX would prioritize Boca Chica GSE when they cannot even get permission to use it for a launch? This is why the pace of GSE work at KSC is accelerating and the work at Boca Chica looks like it is not much more than verification of designs and development of procedures.

  • cloudy

    Speaking of dangerous chemicals, both SLS/Orion and Dragon both use hydrazine for reaction control. This stuff in extremely toxic and as a result is expensive to handle. Does Starship use it at well? There was a higher performance, easier to handle replacement tested in the Green Propellant infusion mission on an early Falcon Heavy launch.

  • Jay

    So I thought they were going to give SLS a fancy paint job and graphics? I see the worm logo on the SRBs on the side. I got to see the wide shot picture of SLS. I guess they gave up on the graphics (the lines).

    Yes, I saw the photos of the lightning strikes. Of course this is the Florida, the lightning capital of the U.S.A.

  • Calvin Dodge

    Starship does not use hydrazine. The current plan is to use gas from the LOX tank, since boil-off will require regular venting anyway

  • Jeff Wright

    Dragon uses hypergols. Starship doesn’t-but it might be a good back-up.

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