The results of a feasibility study for ultrasonic inspection of L-0 blade root inspection are presented. Two linear phased-array probes were used to detect the EDM notches in specific reference blocks and an actual spare blade root. The ray-tracing model was used to develop wedges, to optimize the detection, and to explain detection by mode-converted waves. Data analysis for three techniques was performed using TomoViewTM and 2-D / 3-D layout of blade/block. EDM notches as small as 2 x 0.5 mm could be detected up to 65 mm from the inlet / outlet faces. Larger EDM notches (6 x 2 mm, 9 x 3 mm and 12 x 4 mm) could be detected and sized up to a depth of 120 mm. The sizing accuracy for length is about 1 mm, and 0.5 mm for the height. Representative detection and sizing examples are also included.