Historical Perspectives: Evolution of Recent Mars EDL Systems Development

This presentation was part of the session : Historical PerspectivesSixth International Planetary Probe WorkshopNASA's history of Entry, Descent, and Landing (EDL) -dependent missions has its share of success stories and failures, often both present in any given mission. This paper focuses on the success and failure stories as they unfold in the Mars exploration program, taking lessons from the Jet Propulsion Laboratory's experience. The Mars program's success has depended on work and partnerships shared between many entities that have elevated the challenges associated with the design and development of EDL systems for planetary spacecraft. Current EDL development is reliant on several different organizations whether it's a specific analytical capability, unique facility, or the knowledge of how to design, build, and test a particular hardware component. As part of the developmental process, each of these organizations has influenced and are affected by the evolutionary outcomes. While the EDL subsystem is undoubtedly an integrated part of the overall flight system, its design and development has been well-served by a dedicated team of engineers and analysts, as experienced during the Mars Pathfinder program. At JPL, this organizational philosophy has remained while the structure itself has responded to a greater understanding of EDL and systems engineering in subsequent missions. EDL-focused work performed at partner centers and companies has contributed to learning how the organization operates. The challenge of managing out-of-house EDL development has also led to a rich supply of lessons learned, following the Mars Polar Lander and now the Phoenix Lander program as it approaches Mars entry. A historical snapshot of the four Mars EDL missions between 1995 and 2008 includes the organizational structure, modeling and simulation capabilities, test program highlights, and program development timelines for each mission where information was available. Stories from key JPL personnel involved with each mission serve to connect some of the challenges and lessons learned with the program information while unpacking less obvious system engineering tenets such as team dynamics and communication and system-level integration. While each new EDL development consistently presents new challenges, future EDL-dependent missions can benefit from understanding the historical context that framed past programs and how the evolution of the process has taken place.Jet Propulsion Laborator