Lunar module descent mission design

Abstract

Various lunar descent trajectories were analyzed that include the optimization of the Apollo constrained mission trajectory, a fully optimized minimum energy trajectory, and a optimal, constrained trajectory using current instrumentation technology. Trade studies were conducted to determine the impacts of mission assumptions, pilot in the loop/automated flight demands, and additional constraints for the present recurring missions to the same outpost landing site. For mission design at this conceptual phase of the program, the Apollo pre-mission planning was applied to account for known contingencies (hardware, instrumentation known uncertainties) and unknown unknowns. The mission Delta-V's are presented in a risk form of conservative, nominal, and optimistic range where 90 percent of Delta-V is derived by trajectory analysis and the other 10 percent was derived from a qualitative analysis from Apollo 11 pre-mission planning. The recommendations for the Delta Vs are the following: conservative (Apollo derived) (2262 m/s), nominal (2053 m/s), and optimistic (1799 m/s). Because of the qualitative nature of the results, the degree of autonomy assumed, additional safety considerations for a lunar outpost, and the impact of advanced instrumentation, more in-depth analyses are required to refine the present recommendations. Copyright © 2008 by Alan W. Wilhite, Georgia Institute of Technology.