Lots and Lots of Concerns About SLS & Orion

Artist concept of the Block I configuration of NASA’s Space Launch System (SLS). The SLS Program has completed its critical design review, and the program has concluded that the core stage of the rocket will remain orange along with the Launch Vehicle Stage Adapter, which is the natural color of the insulation that will cover those elements. (Credit: NASA)
Artist concept of the Block I configuration of NASA’s Space Launch System (SLS). The SLS Program has completed its critical design review, and the program has concluded that the core stage of the rocket will remain orange along with the Launch Vehicle Stage Adapter, which is the natural color of the insulation that will cover those elements. (Credit: NASA)

The NASA Aerospace Safety Advisory Panel (ASAP) held a meeting on July 21 at NASA Headquarters in Washington, DC. Below is the section of the meeting minutes that deals with the space agency’s Exploration Systems Development, which includes the Space Launch System (SLS), Orion Multi-Purpose Crew Vehicle and related ground systems.

Exploration Systems Development (ESD)

Dr. George Nield reported on a number of presentations that the Panel heard relating to ESD. The first was from Mr. Bill Hill, Deputy Associate Administrator
for ESD, who provided a list of top concerns, including

  • integrated avionics and software verification and validation (V&V);
  • V&V in general;
  • the budget (specifically, out-­year funding uncertainty);
  • the mobile launcher and outfitting;
  • completion of the European Service Module (SM) for Orion;
  • some of the Space Launch System (SLS) welding operations in the Vertical Assembly Center (VAC);
  • long term sustainability in terms of production and operations sustainability at a planned flight rate of one flight per year; and,
  • Exploration Mission (EM)‐2 mission planning, where the specific tests planned for that mission deliberately have not been identified.

The Panel heard from Mr. George Gafka, ESD Chief of Safety and Mission Assurance (SMA) and Mr. Jeff Williams, who talked about the Cross Program Integrated Hazard Analysis (CPIHA). Two hundred seventy potential hazardous conditions have been identified, and those have been organized further for analysis and for potential mitigation action. That identification and organization has resulted in 75 integrated hazardous conditions being worked. Some of highest risk causes include the possibility of bird strike during ascent and external hydrogen at the pad due to failure to burn off sufficient hydrogen following an on-­pad shutdown.

The Panel also heard from Ms. Jennifer Franzo, the ESD SMA person, who identified some of the elevated program-­only hazard causes. To NASA, “elevated” means, in the 5×5 hazard matrix that looks at the likelihood and severity of something happening, a zone 4 or a zone 3. A zone 4 is something that has a very high likelihood and a catastrophic severity. Zone 3 is something that has a combination of likelihood and severity ranging from very high likelihood with a severe outcome to a moderate likelihood with a catastrophic outcome.

Currently, there is one hazard that has been identified as a 4×5 in the matrix, 33 hazards in the mid‐area, and 4 that have not yet been categorized in terms of likelihood but are considered to be potentially catastrophic. That sounds arresting, but the Panel appreciates that the Program is doing some excellent work in identifying hazards, the likelihood that they are to happen, and the steps that can be taken to address those hazards.

Overall, NASA’s progress on ESD is best represented by work that is not necessarily visible to the public. A considerable amount of hardware has been built and is being integrated and tested and many analyses are being conducted. All of this is leading to a potential EM‐1 launch availability window of September through November 2018.

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