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Complex engineered systems with long life cycles can expect to face operational uncertainty. Two common approaches to maintain system performance in an uncertain operating environment are flexibility, where the system is designed to change easily in response to a change in the operating environment and robustness, where the system is designed to sustain performance despite change. Prior work has examined how to design systems to be either flexible or robust, but so far this work largely assumes that these strategies are implemented during the design phase and that designers know the possible changes that the system will face. However, in practice, many systems face unforeseeable needs and must be modified to sustain value post-production. Through an inductive case study, this paper examines that process: documenting how aircraft were modified post-production to gain new capabilities for close air support in Operation Desert Storm. Consistent with prior studies, it finds that new capabilities can be gained through both changes to form and changes to tactics. Extending this line of work, this study examines the conditions under which each type of change is effective. Additionally, it highlights an important interaction between form and tactical changes that has not been well defined in existing literature.
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Comparative Analysis of Pathways to Changeability
Through an examination of three cases of change in the U-2 platform, this paper compares three pathways to changeability: form changes, operational changes, and cyber changes. Each pathway can lead to change in similar properties of a system but have varying levels of performance and time to implement. For each pathway, we describe the design mechanisms necessary to implement change in that pathway. We analyze the trade-off between performance or extent of change and agility or speed of change and find that form changes offer the highest degree of changeability but take the longest time to implement. Operational changes offer the least degree of changeability but are far quicker to implement. Cyber changes lie in between these two pathways. Understanding the design choices needed and the underlying trade-off of each pathway can enable decision-makers to better select a pathway to change when the need arises. This comparative analysis is especially useful since literature has thus far examined each of these pathways in isolation, not as different paths to the same goal.
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- Award ID(s):
- 2125677
- PAR ID:
- 10448604
- Date Published:
- Journal Name:
- Excerpt from the Proceedings of the Twentieth Annual Acquisition Research Symposium
- Page Range / eLocation ID:
- 148-159
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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