Abstract: A method for testing a structure includes steps of: identifying a three-dimensional position of a surface of the structure relative to a reference frame; transmitting laser light from an output of a transmitter onto the surface of the structure to form ultrasonic waves in the structure and to detect a response to the ultrasonic waves; based on the three-dimensional position of the surface, moving the laser light over the structure along a scan path so that the output of the transmitter is located at a constant offset distance from the surface and that the laser light, transmitted from the output of the transmitter, is directed onto the surface at a constant angle of projection; and based on the response to the ultrasonic waves, determining whether an inconsistency is present in the structure.