A single extra pulse echo was recorded during the last ultrasonic inspection of the rail, nine months before the derailment, in the vicinity of the failure. An examination with handheld ultrasonic testing equipment at the time concluded there was no sizable defect in the rail, even though the evidence suggests that the fatigue cracks existed (to some degree) at the time. The ATSB recommends that the ARTC should address this safety issue.
