The potential for flaws such as disbonds, corrosion, and microcracks in aircraft lap joints and reinforced doublers is a major problem in the aircraft industry today due to the increasing average age of existing aircraft. Several advanced nondestructive testing techniques are being developed for aircraft inspection, including ultrasonics, thermography, eddy currents, X-radiography, and shearography. The focus of this study is to establish a science base for a cost-effective, reliable, and portable ultrasonic system that can be used for nondestructive detection of disbonds in aircraft structure
