TIL! Apparently they do it with an ultrasound instrument: https://www.olympus-ims.com/en/insight/ruckus-composites-inspects-thousands-of-bikes-with-one-ultraso

TIL! Apparently they do it with an ultrasound instrument: https://www.olympus-ims.com/en/insight/ruckus-composites-inspects-thousands-of-bikes-with-one-ultrasonic-thickness-gage/ https://www.olympus-ims.com/en/insight/ruckus-composites-ins...