This investigation, undertaken by OTSI under a Collaboration Agreement with the ATSB, was discontinued.
What happened
An axle in the rear part of train 5WB7 broke as the train entered Casino Yard, derailing the wagon.
The rear four wagons derailed and became detached from the rest of the train. A further four wagons at the rear of the train were derailed after the train came to a stop. A significant amount of track and signal infrastructure was damaged within Casino yard, with no injuries recorded.
The investigation concluded the derailment was due to a broken axle on the 55th wagon (RKPF30311). The metallurgical analysis of axle determined that the failure was due to a fatigue crack on the axle barrel.
Discontinuation
Due to the nature of the failure and the work done by the operator to date, OTSI and the ATSB considered it was unlikely that further investigation would identify any systemic safety issues or further important safety lessons for the enhancement of transport safety.
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