The method used to ultrasonically test the tail pins in-situ was not reliable and resulted in small fatigue cracks going undetected.
The ATSB is satisfied that the action taken by Railcorp to improve the ultrasonic testing procedure addresses this safety issue.
Ultrasonic testing procedures for XPT tailpins have undergone continuous development following both the Broadmeadow and Seymour incidents.
A revised procedure for conducting ultrasonic testing of tail pins has been developed and published on 15 March 2013. The new procedures have been in use for testing tail pins since February 2013.
The latest testing procedure involves three different tests; a single probe along the shaft of the tail pin, two 45 degree angle probes on the head of the tail pin and a single 60 degree angle probe on the head of the tail pin. The latter two tests were introduced after the Seymour incident and are able to detect fatigue cracks that the original test did not.
Additionally, the ultrasonic test provider has undertaken to conduct proficiency examinations and certify their technicians who perform these tests. Certification results will be provided to RailCorp and only certified technicians will be used to undertake tail pin testing on the XPT fleet.
