Abstract:
The objectives of fleet management are typically readiness, availability, and reduced risk and cost. Of course, data management is essential to handle multiple data streams from many platforms. But the heart of successful, proactive fleet management is the science and engineering behind the interpretive analysis used for each "tail number." That is the focus of the present paper. Science and engineering have generally focused on detecting discrete events, especially early in life, then on deciding when a certain "collection" of those events warrants corrective action (e.g., maintenance). This approach has two serious shortcomings for composite material components. First, composite structures rarely fail from damage initiation; they generally fail from damage accumulation and interaction. Second, the limits on performance (e.g., stiffness, strength, and life) are determined by emergent behavior defined by interactive degradation events (from "the bottom") and by the assembly of extrinsic factors including manufacturing, geometry and morphology, load history, and expected performance (from the top). The present paper discusses a rational engineering approach to real-time "tail number" prognosis of composite structures based on the measurement and science-based interpretation of changes in multi-physical material properties. Examples of the approach will be provided and application paths discussed. Relationships to durability, reliability, risk, and liability will also be identified.
