Derailment of freight Train 6413, near Stewart, Western Australia, on 7 August 2007

Executive summary

At about 0400 on 17 August 2007, the 48th wagon of Australian Railroad Group iron ore train 6413 derailed on a right-hand curve in a cutting 595.9 km from Perth in the Stewart to Bonnie Vale section of the Defined Interstate Rail Network in Western Australia. Thirty one wagons in total were derailed and 25 of those wagons were seriously damaged. There were no injuries. The track sustained significant damage and was closed for 4 days.

Train 6413 consisted of three locomotives and 126 wagons loaded with iron ore. It was travelling from Koolyanobbing to the port of Esperance, via Kalgoorlie. Rail traffic in this area includes fast passenger trains, general interstate freight and iron ore trains.

Train 6413 had been authorised by train control to pass a signal that had failed to clear following the passage of the previous train. Both the train controller and the train crew were aware that one possible cause of the signal failure was a broken rail.

The Australian Transport Safety Bureau (ATSB) investigation determined that the derailment occurred when a piece of rail containing a large, previously undetected vertical split head defect, disintegrated under train 6413. A rail insert that had recently been used to replace a section of defective rail found during a routine track inspection probably contained the defect. Alternatively, it was possible, but less likely, that the parent rail on either side of the insert may have contained an undetected vertical split head.

As a result of the investigation, the Australian Transport Safety Bureau identified a number of safety issues concerning train operations, record keeping and rail replacement practices.