In response to this safety issue, Brookfield Rail and/or Aurizon have advised of the following proactive safety action:
- Brookfield Rail and Aurizon will undertake further investigations into lateral harmonic vehicle oscillations induced by cyclic track irregularities.
- Brookfield Rail and Aurizon will engage independent expertise to assist in the identification of the causes of track misalignment associated with lateral harmonic vehicle oscillation, including analysis of contact band wear, sleeper voiding, rolling contact fatigue and a review of bogie hunting video evidence.
- Brookfield Rail and Aurizon will fit instrumentation to a WOE class wagon for examination of lateral harmonic vehicle oscillation.
- Brookfield Rail and Aurizon will support RISSB in a review of track geometry standards in relationship to combinational and cyclic track defects.
- Brookfield Rail will investigate the acquisition and installation of wayside equipment capable of monitoring the onset of lateral harmonic vehicles oscillation across their network. This will include field testing with the intent of identifying any need for altering current operating parameters of fleets across the network.
- Brookfield Rail and Aurizon on its ‘Joint Technical Committee’ have added an ongoing item ‘Status of follow-up investigations’.
- Brookfield Rail will fully capture rail profile details for all future derailments of this type to assist with computer modelling.
- Brookfield Rail and Aurizon will ensure that mapping of a derailment site is completed prior to the restoration process taking place.
- Aurizon will ensuring that all locomotive data and video footage is captured (quarantined) following serious incidents/derailments.
While the ATSB is satisfied that the actions proposed by Aurizon and Brookfield Rail will, when fully implemented, adequately address this safety issue, there remains a broad opportunity for rolling stock providers and rail transport operators to address the future risk associated with the development of resonant dynamic vehicle behaviours. The ATSB is therefore issuing the following Safety Advisory Notice.