control. Others commented that information on the manufacturing processes, not just the CAD/CAM designs, is being lost. Dr. Stevens added that a significant issue is that some portion of the data associated with the design of processes, specific configurations, and so on is not owned by the Air Force. There is growing recognition of the importance of capturing key design and production data for the long-term sustainment of aircraft and other complex defense systems.
Referring to the right-hand side of Figure 3, Dr. Stevens said that capturing NDE/I data for individual systems as they go through maintenance during their operational lives is also an essential part of the cradle-to-grave digital thread concept.
Data from all three phases represented in the figure—design, production, and operational maintenance—will be necessary to enable condition-based maintenance and to have a digital representation (digital twin) of each physical system (e.g., each aircraft). The Digital Thread Sustainment Focus at AFRL, which is aimed at integrating data, models, and simulations throughout the system life cycle, includes the following objectives:
• Extending configuration management to include material properties and dimensional variations from production, modifications, and repairs.
FIGURE 3 Air Force manufacturing technology concept of the cradle-to-grave digital thread. Digital thread activities include generating, capturing, organizing, and utilizing relevant data and information. SOURCE: Katherine Stevens, AFRL, “AFRL and materials issues,” presentation to the committee on July 23, 2012, Slide no. 21.