Identification of Material Damage Precursors Using Novel NDE Hardware

Widespread damage in aging aircraft is becoming an increasing concern as fleet operators are extending the aircraft service increasing the risk of crack-like damage of aircraft components. Predicting the exact fatigue life is a difficult process and fatigue life prediction based on crack length measurements can be grossly inaccurate mainly because the appearance of these cracks typically occurs very late in fatigue life. Thus, to improve remaining useful life prediction of structural components the study of microfeatures called damage precursors is critical. During Phase I program Luna has demonstrated the feasibility of a portable system for nonlinear measurements on aircraft components and for prediction of the remaining useful life. The inspection system is capable of classifying fatigue life of aluminum components for Army maintainers with 95% confidence intervals in steps of 10% of remaining useful life. The primary objective of the Phase II program is to develop an effective and efficient system to provide accurate and reliable information for the remaining useful life metallic aircraft components found in propulsion systems. Phase II effort will include prototyping the fatigue inspection system to maximize performance and capability, while focusing on minimizing cost, weight, size and meet the portability goal.