A “smart-structure”, as illustrated in Figure 1, is defined as a self-diagnostic airplane, i.e., an airplane that has the ability to detect, locate, quantify and assess the impact of precritical and larger structural damage in real-time. NDI techniques to achieve this objective must be accomplished and interpreted in flight. Optical fiber strain sensors and next generation computers have the potential to meet this requirement. A damage detection concept (DDC) must be developed to interpret the strain data measured.