Carbon fiber composite aerospace structures are growing in prevalence due to decreasing costs and high performance; fuel efficiency and strength. However, nondestructive testing systems for quality control (QC) of finished structures remains expensive and cumbersome, primarily accomplished through the use of ultrasonic squirting systems which replicate the effects of immersion ultrasound. While these systems provide useful and detailed information, their practical use is limited and cannot keep up with demands for increased volumes of composite materials for the growing spacecraft, commercial, and military aerospace industry. Non-contact ultrasound (NCU) is a growing field, but until recently has primarily been used for quality control of flat materials or research and development for curved structures. However, through the combination of sophisticated robotics and high sensitivity non-contact ultrasound systems, a practical, high-performance method of final inspection is now available for composite aerospace products. The Ultran Group, a non-contact ultrasonic product manufacturer and Genesis Group, a robotic systems integrator, have partnered to create and deploy industrial non-contact systems for high-resolution QC of carbon fiber composite structures, such as attenuative and multi-layer materials. Initially implemented for QC of rocket payload fairing structures, the configuration of these systems is in through transmission. By utilizing efficient high sensitivity noncontact ultrasonic transducers and systems, the signal to noise ratio is boosted, enabling inspection of very thick substrates with high acoustic attenuation. However, for the purpose of detecting delamination between the skin and core of multi-layer panels, a same-side pitch-catch configuration is also under development. This exciting new application of advanced technology presents a new modality for non-destructive inspection (NDI) of finished aerospace structures.

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