Disclosed is a calibration system and method for a phased array ultrasound pipe inspection system, in which reliable calibration is obtained for notches at all angles using only a small number of notches for the calibration. The method comprises a one-time normalization step and a system calibration step which may be performed at regular intervals. Ultrasound transmission is in a single diverging beam for each aperture, while reception is selective for multiple well-defined reception angles. During the normalization step, plots of maximum response vs reception angle are plotted for each notch, and a normalization curve is constructed by fitting the maxima of these plots. The normalization curve is used to derive calibration targets at specific reception angles for specific calibration notches, which are then used for the system calibrations.
