A Guide for Evaluating Spacecraft Environmental Control & Life Support Systems (ECLSS) Technology Developments



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51st International Conference on Environmental Systems


Environmental Control and Life Support Systems (ECLSS) are the core of any human spacecraft or habitat and are key to the astronaut's survival during missions. NASA continues to invest in the development of ECLSS technology that more efficiently recycle air, water, and waste. These advancements are needed to enable longer duration Artemis missions to the Moon or Mars and reduce dependency on Earth. Objectively evaluating the content of a technical portfolio is critical to identifying and advancing the most technically relevant and/or promising technology solutions, particularly in limited resource scenarios. Here we define four types of technical portfolio evaluations: 1) Technology Down-Selects where one or more technologies are selected over others within the same trade space (for development or flight), 2) Technology Continuation Reviews where a technology's relevance and development progress is weighed against stand-alone metrics and the risks of continued development, 3) Technology Flight Necessity Assessments to determine whether a flight demonstration is required to meet critical performance goals, and 4) Flight Demonstration Readiness Assessments to determine whether the technology is technically ready to be considered for flight demonstration. Historically, the processes used to evaluate technologies within the ECLSS portfolio have varied from project to project. Therefore, an assessment was performed to improve consistency and transparency of ECLSS technology evaluation processes within NASA. This involved evaluating the processes employed on historical NASA projects, and those used in industry and other government agencies to identify the most relevant and useful aspects of each. The product is a guide to quantitatively and objectively evaluate ECLSS technology developments, and case studies were performed using the new guide on previously completed technology development projects. The outcomes were compared, and findings are reported in this paper along with a discussion of how this new guide will be applied for future NASA ECLSS technology projects.


Darnell Cowan, NASA, US
Morgan Abney, NASA, US
James Broyan, NASA, US
Jay Perry, National Aeronautics and Space Administration, US
Lance Delzeit, NASA, US
Marit Meyer, NASA, US
Orlando Melendez, NASA, US
David Williams, NASA, US
ICES501: Life Support Systems Engineering and Analysis
The 51st International Conference on Environmental Systems was held in Saint Paul, Minnesota, US, on 10 July 2022 through 14 July 2022.


ECLSS, System Engineering, Down-select, Technology, Flight