Analyzing spaceflight residual risk acceptance decisions before launch

Abstract

This paper will examine the typical decision process that National Aeronautics and Space Administration (NASA) project management team members utilize to rank and then accept residual risks before the launch of a spacecraft. Interviews of two flight project management teams at NASA's Goddard Space Flight Center (GSFC) were conducted to understand the structuring of these decisions. Decision attribute preferences were elicited using a lottery technique and a multi-attribute preference model (MAPM) was constructed. MAPM model ranking was consistent with the actual project management team residual risk ranking as well as the ranking determined by the project's risk scoring scheme. While we found differing risk acceptance behaviors among project team members, the MAPM model generally agreed with the team's actual ranking decisions. However, the MAPM model showed incongruences between the risk scoring scheme ranking and model outputs in the moderate risk region as compared to the GSFC risk scorecard, which may point to a potential area of disagreement between project management team members when moderate risks must be accepted before flight.