A RANGE of factors relating to weight, braking equipment, track conditions and operational procedures led to a destructive grain train derailment, according to the ATSB’s final incident report.
Shortly before dawn on 15 December 2020, the crew of a Qube-operated grain train, consisting of two locomotives, 40 loaded wagons and one empty wagon, lost control on the descent into Unanderra on the Moss Vale to Unanderra rail line in NSW.
During the runaway, the train reached 100 km/h on a 30 km/h section of steep, winding track.
The train subsequently separated at two points, and 39 of the trailing wagons derailed and were destroyed, causing substantial damage to track infrastructure. Fortunately, the ATSB notes, the locomotives and first two wagons remained on the track, and the crew – the driver and driver’s assistant – were able to avoid physical injury, stopping the train towards the bottom of the embankment.
A final report from the Office of Transport Safety Investigations, which conducts NSW rail investigations on behalf of the ATSB, notes 13 findings – either contributing factors, or factors which increased risk in the accident.
“Among the findings, the investigation identified several factors led to the train’s braking being ineffective, contributing to the runaway,” OTSI’s acting chief investigator Jim Modrouvanos said.
“It was likely that several individual wagons were over their allowable weight limit, and the train as a whole was near, but likely not over its own maximum allowable tonnage,” he noted. “In addition, variability in the braking capability between wagons likely reduced the braking effort on some wagons during the steep descent. Low track adhesion caused by wet rail and track contaminant also affected train handling and locomotive dynamic braking.”
The report found some of the driver’s decisions on the morning of the accident were likely affected by fatigue, but also that Qube’s relevant operational procedure did not account for locomotive configurations that maintained locomotive dynamic braking during emergency applications.
The ATSB lauds a strong response by Qube and other operators to a resulting OTSI safety notice and subsequent recommendations.