Introduction of composites by the aerospace industry has brought benefits, like fuel efficiency and improved aerodynamics, among others. However, the production and operation of aircraft relies on the accurate and timely detection of defects with Non-Destructive Testing (NDT) techniques. There is a concern regarding the applicability of conventional NDT techniques, originally designed for metal-based aircraft, to composite structures. The challenge comes from the fact that composite and metal parts have different responses to NDT and they generally display different failure mechanisms. Metals are subject to corrosion, which is not a concern for composites. On the other hand, the primary concern for layered composites lies in delamination, which is non-existent in metals. One common NDT is Active Thermography (AT). Thermography based multi-point laser heating is still in the development stage and cannot provide a viable alternative to Fourier Transform Infrared (FTIR) spectroscopy. FTIR is the most viable tool for detection of the actual fact that heat exposure took place and provides certain indications on the amount of heat the surface was subjected to. Nevertheless, our system detects the effective volumetric response of the sample and we are confident that in future it will become a viable alternative to surface based techniques.

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