Trade Study Results for a Second-Generation Reusable Launch Vehicle Composite Hydrogen Tank

As part of the Space Launch Initiative (SLI) Composite Tank program, trade studies were conducted to determine the optimum composite cryotank design for a next-generation reusable launch vehicle (RLV), including material selection, tank wall construction, cryoinsulation, adhesives, liner materials, and tank tooling/manufacturing approach. Requirements were established and assumptions made based on input from NASA and from systems engineering efforts at Boeing and Lockheed Martin. For each aspect of the study, a Boeing/NASA technology team typically started with initial brainstorming that identified dozens of candidates. The long lists were then screened using limited quantitative analysis, logical arguments based on experience, and general engineering knowledge to reduce the number of options to a manageable number for more detailed analysis. An extremely large amount of data and information was generated in the program, and detailed reports are available from NASA. This paper is an overview of the results.