Introduction of composites for aircraft fabrication has given the opportunity to all researchers and original equipment manufacturers to design a lightweight structure that will reduce both fuel consumption and harmful emissions. Reliability and cost of implementing structural health monitoring (SHM) systems are two critical parameters for the utilization of composite materials in the aviation industry. SHM of composite material components in the aviation industry not only lessens the downtime of aircraft but also enhances the possibility of damage detection in order to avoid severe failure. This article presents a case study of SHM systems that has been developed from research and implemented for the inspection and safety of recent aircraft structures. Compulsory components required for proper working of an SHM system and the basis and classification of defects in composite material components of aircraft are thoroughly explained in this article. Furthermore, characterization of SHM techniques (on the basis of functioning, advantages, and limitations) for crack detection and challenges of SHM systems are also part of this case study. An experimental work and its results have been well expressed regarding guided wave inspection using two different types of fiber-optic sensors for quasi-isotropic carbon fiber–reinforced plastic laminate. The ultimate goal of this article is to highlight the current challenges of SHM and promote the concept that SHM has great potential for research in the aviation industry.
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