On 30 December 2013 at 1547, train 2DA2 (travelling from Darwin to Adelaide) derailed while traversing the points into the loop line at Union Reef. Shortly beforehand, the train crew had commanded the points to reverse for entry into the loop line, however the automated points system was unable to complete the reversal movement – leaving the points in an unsafe open position.
There were no injuries sustained during the derailment, but about 100 m of track infrastructure was damaged, and the main line between Darwin and Tarcoola was blocked for about 5 days.
What the ATSB found
The ATSB found that the northern points at Union Reef had most likely failed to fully transition for the crossing loop because of ore product build up and inadequate lubrication. It had been previously recognised that this location was prone to ore product build up in the four foot and points, but the inspection and maintenance regime had not been adjusted to address this localised issue and the potential increase in risk to rail operations that it presented.
The ATSB also found that the train crew were distracted by several conflicting responsibilities at a time when they were also expected to be preparing for entrance to the crossing loop. While the driver was operating the train at a speed he considered appropriate for traversing the points, he did not expect the point enhancer to remain at red (or the points to be unsafe), and as such, he was unable to stop the train before the open points. Reduced sighting of the point indicator/enhancer due to track curvature and track side vegetation had limited the opportunity for early identification and response to the red indication, even though a repeater indicator had provided prior warning as to its unsafe status.
What's been done as a result
Following this occurrence, Genesee Wyoming Australia (GWA) reviewed the reliability, inspection and maintenance frequency of motorised self-restoring points machines. Similarly, with a view to identifying and addressing any increased risk in these locations, GWA specifically undertook to monitor the functionality and performance of track/points exposed to the accumulation of mining products.
Responding to the human element, GWA advised that a Critical Safety Zones program will be introduced to provide clarification to train crews on acceptable speeds and necessary caution required when approaching points with reduced sighting distances.
Rail operators and train crews are reminded that distraction can have a profound impact on safety during critical phases of train operation. To combat situations where signals (often the final defence against an incident) are affected by reduced sighting distances, strengthened guidance should be given to train crews on ensuring that appropriate approach speeds are established and maintained throughout the critical areas.