NASA is now planning for the Space Launch System (SLS) core stage assigned to the…
  • NegativeInf@lemmy.worldEnglish
    3·
    1 year ago

    The article discusses the ongoing efforts to overcome supply chain and welding issues to complete the Artemis II Core Stage by mid-December 2023. Here are the key points:

    1. Core Stage-2 Progress:

      • The four RS-25 core stage engines were installed at Michoud Assembly Facility (MAF) in New Orleans in September 2023.
      • Despite supply chain issues and a new weld tool issue delaying the liquid oxygen (LOX) tank for Core Stage-3, the target completion for Core Stage-2 remains late 2023.
      • The final assembly includes integrated functional testing (FIFT), aimed to be completed by mid-December, before shipment to Kennedy Space Center (KSC).

    2. Core Stage-3 Production:

      • It’s undergoing production at MAF and KSC, with the engine section already at KSC.
      • A welding issue with the LOX aft dome has stalled the completion of the LOX tank, impacting the overall schedule.
      • Despite the delay, the target completion for Core Stage-3 is end of 2024 or early 2025, aligning with the Artemis III mission’s December 2025 launch date aspirationally.

    3. New Production Plan:

      • Beginning with Core Stage-3, final assembly moves to KSC in a vertical production cell, differing from the horizontal assembly at Michoud for the first two units.
      • This change provides more access and flexibility for potential late-stage work or reworks.

    4. Core Stage-4 Update:

      • Structures are under progress at MAF, with the engine section structure expected to ship to KSC in spring 2024.

    5. Challenges Encountered:

      • Supply chain issues, particularly with a LOX feedline segment which had to be reworked at a supplier, contributed to delays.
      • Welding issues with the LOX aft dome in Core Stage-3 have been ongoing for several months, though a resolution is nearing.

    6. Strategies to Overcome Challenges:

      • Teams have utilized the delay time to address other potential issues, like the LOX prevalves, to prevent further delays post-shipping to KSC.
      • The change in assembly orientation and location (from MAF to KSC) from horizontal to vertical is aimed to streamline the final assembly process and provide more flexibility.

    The progression of Core Stage-2 and 3 is critical for the scheduled lunar missions under the Artemis program, with each stage facing its unique challenges and adaptations to keep the program on track.