TECHNISCHE UNIVERSITÄT MÜNCHEN Lehrstuhl für Raumfahrttechnik Heritage Technologies in Space Programs – Assessment Methodology and Statistical Analysis Dipl.-Ing. Univ. Andreas Makoto Hein Vollständiger Abdruck der von der Fakultät für Maschinenwesen der Technischen Universität München zur Erlangung des akademischen Grades eines Doktor-Ingenieurs (Dr.-Ing.) genehmigten Dissertation. Vorsitzender: Prof. Dr.-Ing. Mirko Hornung Prüfer der Dissertation: 1. Prof. Dr. rer. nat. Dr. h.c. Ulrich Walter 2. Prof. Edward Crawley, Ph.D. Massachusetts Institute of Technology, USA Die Dissertation wurde am 27.06.2016 bei der Technischen Universität München eingereicht und durch die Fakultät für Maschinenwesen am 30.10.2016 angenommen. This page intentionally left blank. Acknowledgments First, I would like to express my deep gratitude towards Prof. Walter for accepting me as a PhD student and giving me the liberty to pursue this specific PhD thesis topic. In particular, I would like to express my gratitude for the support during the final phase of the thesis that made a lot of things easier. Next, I would like to express my gratitude towards Prof. Ed Crawley and Bruce Cameron for hosting me at the MIT System Architecture Lab in 2012/2013 and in particular Ed for making your way to Munich for acting as an examiner of this thesis. The staff of the Institute of Astronautics played an important role in my PhD experience. The great team spirit and the passion for spaceflight will remain in my memory. With respect to this thesis, I would express my particular gratitude towards Alex Höhn, who helped me countless times with his feedback and advice. I would also like to thank Philipp Hager for our years we have spent in the same office and who helped me a lot during times when things did not go smoothly. I also think that I would not have dared doing a lot of things without you as a role model. Further, Martin Langer for all the conversations on small satellites and interstellar travel, Markus Brandsätter and Carolin Eckl for all the conversations on computer science and systems engineering, and all the current and former members such as Manuel Czech, Matthias Raif, and Andreas Peukert who were vital for my integration into the institute. I would also like to thank Felicitas Mittereder and Alborz Bekhradi for their help in economectrics. Your advice was very important for conducting the statistical analyses in this thesis. During my time at MIT I had great labmates: Alexander Rudat, Daniel Selva, Wen Feng, Peter Davison, Sydney Do, Narek Shougarian, Morgan Dwyer, Sreeja Nag, Koki Ho and others. Thank you very much for all the conversations on systems architecting and the nice atmosphere! My gratitude also goes to my students that I had the privilege to supervise. Your work was indispensable for maturing my research. It is not possible to list all your names here but I learned much from each one of you. I would like to mention one particular student, Jan Schröder, who is no longer with us, but who let me experience the deep satisfaction of seeing people grow. I will not forget about you. I would also like to thank all the numerous interviewees from industry and academia that have spent their valuable time answering my questions and reviewing my work. Your help was vital for this thesis! To my colleagues from the Initiative for Interstellar Studies, Icarus Interstellar, and WARR who have accompanied me during my PhD years: Without the time I have spent with you, this thesis would definitely look different. Thank you! This thesis would also not be what it is without my friends who supported me during all these years with all its ups and downs. It is a privilege to share my time with you! In particular, I would like to thank in alphabetical order Dave, Jan, Mik, Tanja, Walter, Wilfried, and Yuriy. My particular gratitude goes to Hélène for her patience and support during all the evenings and weekends when I worked on this thesis. I have learned so much from you during this time! Finally, and most importantly, I would like to express my deepest gratitude for my parents. Without your unconditional support during all these years, I would not be here where I am! This thesis is dedicated to you! This page intentionally left blank. Abstract An established approach to cost and risk reduction in system development programs is the use of heritage technologies. A heritage technology is defined as a proven technology, reused in a new use context, in an unaltered or adapted form. Heritage technologies are particularly relevant for space systems development programs, as their development costs are usually high and stakeholders risk-averse. Nevertheless, numerous space programs encountered problems linked to improper ‘management’ of heritage technologies when reused, i.e., improper use, implementation or adaptation. Improperly managed heritage technologies can lead to cost and schedule overruns, or even failure in the reuse application. Currently, the applicability of heritage technologies is mostly assessed ad-hoc. The existing assessment approaches are deemed to be insufficient for providing decision-makers and analysts with ample guidance on the applicability of heritage technologies. This thesis presents a methodology for assessing heritage technologies in the early phases of development, taking the new use context of the technology, its necessary adaptations and modifications, as well as technological capabilities of the implementing organization into consideration. For illuminating the relationship between the use of heritage technologies and the performance of space programs empirically, a statistical analysis is performed. The methodology focuses on the early phases, where most of the technology selection takes place. A 3-component framework is developed that serves as the theoretical basis for the statistical analysis and the methodology. The framework consists of a systems architecting framework, a technology framework, and a verification, validation, testing, and operation framework. Based on the concepts developed in the framework, a statistical analysis is performed. Using multiple regression with control variables, a statistically significant relationship between heritage technology and specific development cost / development duration was confirmed. No statistically significant relationship between heritage use and development cost overrun / schedule overrun could be confirmed. Based on the framework and results from the statistical analysis, a methodology for assessing heritage technologies in the early phases is developed. It allows for identifying potential compliance issues of the heritage technology with respect to changed requirements and constraints. Estimating the impact of modifications is performed via design structure matrices and a graph-edit-similarity algorithm. Furthermore, a heritage metric is presented that can be used for measuring heritage with respect to a new application. Finally, the methodology also allows for assessing technological and organizational capabilities. The methodology is validated by three space system case studies: 1) a CubeSat component technology, 2) a high- pressure tank technology for the Ariane 5 launcher, and 3) the Saturn V and Space Launch System technology. From the presented work it can be concluded that the methodology can be systematically applied to various types of space systems at different levels of decomposition. The heritage metric provides a rough estimate of the heritage of a technology for a new application and context. The statistical analysis confirmed that in general using heritage technologies significantly reduces specific development cost and development duration. As future work, the developed methodology could be extended to other domains such as automotive engineering, aeronautics, and medical engineering, where heritage also plays an important role. Page V This page intentionally left blank. Zusammenfassung Ein etablierter Ansatz Kosten und Risiken in der Systementwicklungsprogrammen zu senken ist der Einsatz von Heritage Technologien. Eine Heritage Technologie ist definiert als eine erprobte Technologie, welche in unveränderter oder veränderter Form, in einem neuen Kontext wiederverwendet wird. Heritage Technologien sind besonders relevant in Entwicklungsprogrammen für Raumfahrtsysteme, da deren Entwicklungskosten besonders hoch sind und deren Stakeholder besonders risikoscheu. Jedoch traten in zahlreichen Raumfahrtprogrammen Probleme im Zusammenhang mit unangemessener Handhabung von Heritage Technologien auf, einschließlich in deren Übertragung, Implementierung, und Verwendung. Eine unangemessene Handhabung kann zu Überschreitungen des Budgets und der Projektdauer, oder sogar zum Ausfall in der neuen Anwendung führen. Derzeit wird die Übertragbarkeit von Heritage Technologien größtenteils ad-hoc bewertet. Es wird festgestellt, dass die existierenden Bewertungsansätze unzureichend sind um Entscheidungsträger und Analysten bei der Bewertung von Heritage Technologien zu unterstützen. Diese Arbeit präsentiert eine Methodologie für die Bewertung von Heritage Technologien in den frühen Phasen der Systementwicklung, unter Berücksichtigung des Kontexts der Technologie, deren notwendigen Anpassungen und Modifikationen, und technologischen Fähigkeiten der Organisation welche die Technologie entwickelt und hergestellt hat. Um den Zusammenhang zwischen der Verwendung von Heritage Technologien und der Performanz von Raumfahrtprogrammen zu beleuchten wird eine statistische Analyse durchgeführt.