File:LSAMDesign IAC06 MIT.doc

IAC-06-D.2.7 / A.3.7.06 Conference Paper LSAM Design Options

ABSTRACT The Lunar Surface Access Module (LSAM) is one of the major elements in NASA’s lunar exploration architecture as outlined in the Exploration Systems Architecture Study report from 2005. As the primary functionality of the LSAM is to capture the Crew Exploration Vehicle (CEV) into lunar orbit and deliver crew and cargo from lunar orbit to the lunar surface, the LSAM interfaces with the Ares V launch vehicle and the CEV, and has significant impact on the overall operations and performance of the lunar exploration system. This paper presents an analysis of the high-level architecture and design space for the LSAM system. The analysis involves two steps: first, a large number of LSAM concepts are generated and evaluated for different types of surface missions. Based on this architectural analysis, a subset of interesting concepts is selected. For these interesting architectures a detailed analysis is carried out assuming a fixed Ares V TLI capability for single-launch sortie and dedicated cargo delivery missions. Based on results from both steps, specific recommendations are derived. These are baselining a single launch for lunar sortie missions, including the capability for extended pre-descent loiter in lunar orbit, and utilizing two-team lunar surface shift operations for reduction of crew compartment and airlock volume requirements. Furthermore, a number of LSAM concepts beyond the two-stage lander in the ESAS report are described which may warrant further consideration; a subset of these concepts involve stages that are dropped on the lunar surface prior to landing.