A Value Proposition for Lunar Architectures Utilizing Propellant Re-supply Capabilities

Paper number

IAC-07-A3.I.A.19

Author

Mr. James Young, Georgia Institue of Technology, United States

Coauthor

Dr. Alan Wilhite, United States

Year

2007

Abstract

The NASA Exploration Systems Architecture Study (ESAS produced a transportation
architecture for returning humans to the moon affordably and safely while using commercial
services for tasks such as cargo delivery to low earth orbit (LEO). Another potential utilization of
commercial services is the delivery of cryogenic propellants to LEO for use in lunar exploration
activities. With in-space propellant re-supply available, there is the potential to increase the
payload that can be delivered to the lunar surface, increase lunar mission durations, and enable a
wider range of lunar missions. The addition of on-orbit propellant re-supply would have farreaching
effects on the entire exploration architecture. Currently 70 percent of the weight delivered to
LEO by the cargo launch vehicle is propellant needed for the TLI burn. This is a considerable
burden and significantly limits the design freedom of the architecture. The ability of commercial
providers to deliver cryogenic propellants to LEO may provide for lower costing and better
performing lunar architecture.

The work presented here will be the culmination of a two-year study to investigate how the
use of on-orbit propellant re-supply would affect future exploration missions. This study
specifically focuses on how performance, cost, reliability, mission success and extensibility are
affected when this capability is added to the current NASA lunar architecture. A series of
architecture alternatives are investigated to better understand how this capability affects the design
of the entire architecture. These alternatives consider different propellant combinations, which
elements perform the LOI and TLI maneuvers, which elements are re-fueled in LEO, and when
boil-off mitigation is or is not used. These different alternatives are compared against the baseline
NASA lunar architecture using a multi-attributed decision making technique that incorporates
each Figure of Merit. Finally, a sensitivity study will be conducted to investigate how changes in
the design inputs and assumptions affect the results of the study. Selecting a design that
consistently performs well across the entire sensitivity study will provide a more robust design
that will continue to perform well if design changes are made during the final steps of the design
process.

Abstract document

IAC-07-A3.I.A.19.pdf

Manuscript document

IAC-07-A3.I.A.19.pdf (🔒 authorized access only).

To get the manuscript, please contact IAF Secretariat.