Driven by high strength‐to‐weight ratios and advanced design flexibility, the application of composite structures in the aerospace industry is growing exponentially. A low thermal conductivity and thermal expansion coefficient give an edge when it comes to applications requiring stringent thermal loads, especially in aircraft engines. It is thus necessary to characterize, qualitatively and quantitatively, the behaviour of composite structures under harsh thermal loads for their certification. In this paper, characterization of multiple heat damages on 30 × 30 cm2 composite panels (16 layers, 00 unidirectional, and carbon fibre composite panel) is carried out by using visual inspection, ultrasound (a‐ and c‐scans), and shearography. It has been observed that shearography, being a fast and noncontact technique, offers multiple advantages for sizing thermal damages. Primarily, it could be applied as a technique for a quick and effective inspection of composites, in turn, increasing the productivity of the quality assurance cycle.