LUNA INNOVATIONS INCORPORATED — Department of Defense SBIR Phase I: Widespread damage in aging aircraft is becoming an increasing concern as both civil and mi

Description

Widespread damage in aging aircraft is becoming an increasing concern as both civil and military fleet operators are extending the service lifetime of their aircraft and increasing risk of crack-like damage of aircraft components. The scientific community found that fatigue damage initiation occurs at micro-features called fatigue damage precursors (FDP). This requires that fatigue crack growth analyses address the influence of usage on FDP and eventual macro-scale crack growth. Predicting the exact fatigue life is a difficult process and fatigue life prediction based on crack length measurements can be grossly inaccurate. In addition, the appearance of these cracks typically occurs very late in fatigue life under high cycle fatigue conditions. Thus, to improve remaining useful life prediction of structural components the study of FDP is critical. In order to address this need, Luna is teaming with Arizona State University to develop advanced ultrasonic and eddy current evaluation techniques with potential application for structural health monitoring. The proposed method is based on using multi-scale modeling with combined linear and nonlinear ultrasonic parameters and eddy current measurements of electrical properties to predict the damage state and remaining service life of aircraft structural components.