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Rail flaws can be initiated either from manufacturing or service-related anomalies. These flaws may lead to train derailment while in service if not detected timely. Traditional non-destructive testing (NDT) techniques are mainly contact-type and have low inspection speeds. Laser ultrasonic testing is an advanced NDT that provides non-contact, broadband, and highly sensitive inspection. Meanwhile, Rayleigh waves suffer little attenuation during propagation and travel long distances on curved surfaces like rail. Therefore, this research proposes a design of a fully non-contact laser-based rail inspection system to detect surface and subsurface defects at different parts (head, web, and foot) of the inspected rail track. The laser-based thermoelastic generation of narrowband Rayleigh waves was investigated using the finite element method (FEM). The experiments were performed on defective rail samples with artificial …