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An Engineering Systems Analysis of Crewed Lunar Exploration Habitation Alternatives

An Engineering Systems Analysis of Crewed Lunar Exploration Habitation Alternatives. Arthur Guest December 9 th , 2008. Presentation Outline. System Overview & Design Alternative Lunar habitat development & deployment Dealing with an uncertain flight rate and program lifetime

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An Engineering Systems Analysis of Crewed Lunar Exploration Habitation Alternatives

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  1. An Engineering Systems Analysis of Crewed Lunar Exploration Habitation Alternatives Arthur Guest December 9th, 2008

  2. Presentation Outline • System Overview & Design Alternative • Lunar habitat development & deployment • Dealing with an uncertain flight rate and program lifetime • Decision analysis • Dealing with an uncertain monetary return from lunar exploration • Lattice analysis • Summary

  3. System Overview & Design Alternatives • The system consists of the habitation modules which are delivered to the lunar surface to enable long-duration stays • Eight year program with up to two flights (crew or cargo) per year • Two alternatives: • 1) Develop interdependent connected habitats • Advantage: lower complexity -> lower cost • Disadvantage: cannot support crews until all modules are assembled • 2) Develop independent stand-alone habitats • Advantage: can support crews for shorter durations before all elements are delivered • Disadvantage: higher complexity -> higher cost OPTION ONE Cost $1,955 USD Million Duration Profile 1 module = 0 days 2 modules = 0 days 3 modules = 0 days 4 modules = 0 days 5 modules = 0 days 6 modules = 180 days OPTION TWO Cost $3,040 USD Million Duration Profile 1 module = 30 days 2 modules = 60 days 3 modules = 90 days 4 modules = 120 days 5 modules = 150 days 6 modules = 180 days

  4. Dealing with an uncertain flight rate and project lifetime • NASA’s crewed lunar exploration architecture is heavily affected by changing in the United States’ political landscape • Therefore, chance every four years: • 1) The program can be cancelled or initiated • Estimated 33.3% probability • 2) The program flight rate can be reduced to 1 flight/year • Estimated 50.0% probability • 3) The program flight rate can be left at 2 flights/year • Estimated 16.7% probability • Decision 1 – Fixed or flexible • Fixed option must deliver all six habitats before crew is delivered • No decisions • Flexible option can decide the number of habitats to deliver each four-year period that increases expected return • Habitats delivered before any crew flight during four-year cycle

  5. Decision Tree Expanded (1/3)

  6. Decision Tree Expanded (2/3)

  7. Decision Tree Expanded (3/3)

  8. Decision Analysis Results • Fixed option has an expected value of return of 360 days • Flexible option has an expected value of return of 416.7 days

  9. Looking more in depth into the return • Fixed – deliver six habitats before delivering crew • Flex 1 – deliver minimum amount of habitats per cycle • Flex 2 – deliver maximum amount of habitats per cycle • Cost/benefit ratio • Fixed = $1,955M/360days = $5.43M/day • Flexible = $3,040M/416.7days = $7.30M/day

  10. Dealing with an uncertain value of return • How do you value the monetary return from each year of extended crewed exploration on the Moon? • Studies of the Apollo era showed that the return from each year of exploration was ~$4B • Starting point for the expected return for future exploration • At first order, NASA’s budget can be taken as a reflection of public interest/return • It’s variation can be used to predict the variation in the value of exploration n = 1.22% s = 8.91%

  11. Setting up the lattice analysis • Analyzing the budget, we can set up a lattice as shown below • Starting value: $4B, p=0.568, d=0.915, u=1.093 • We will use this to analyze the fixed alternative • Habitats delivered from 2020-2022 • Crewed exploration starts in 2023

  12. Calculating the ENPV for the fixed alternative • Costs of operations • Capital expenditure: $1,955M + $3,000M • Annual crewed launch cost: $3,000M

  13. Value of an option to abandon the project

  14. Summary • Examined two alternatives for deploying lunar habitation modules • Fixed: Deliver six interdependent habitats before delivering crew • Flexible: Deliver up to six independent habitats as required • Flexible option provides greater expected return in regards to crew-days • Higher cost/benefit ratio • Fixed option provides positive ENPV • Option to cancel program early worth $5M

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