The ATSB determined that a combination of hot weather and track disturbance activities resulted in a misalignment of the track and a freight train derailment.
The derailment occurred on 12 February 2013 at Locksley, near Seymour in Victoria. The train, an intermodal freight train, was hauling 33 wagons from West Gate Ports, Melbourne through to Harefield in New South Wales. After traversing the Nagambie-Locksley Road level crossing near Locksley, both drivers saw a large track misalignment ahead of them. The driver throttled off from a speed of 108 km/h in an attempt to ride through the misalignment.
Hot weather in the period leading up to the derailment, along with the trains travelling along the track, probably combined with maintenance activities to affect the concentrations of stress within the track, causing it to buckle.
The train continued over the misalignment and travelled a further kilometre, at which time the driver assumed that the train had passed through safely when he noticed a significant reduction in brake pipe pressure—a possible indicator of a train parting or a derailment. The driver brought the train to a halt, then inspected the train and found that the rear eight wagons had derailed. The last three wagons, though still coupled to the train, had progressively dropped away off the track embankment with the last wagon having completely slipped to the bottom of the formation.
The ATSB investigation found that the track misalignment was most likely the cause of the derailment. Investigators identified several factors that would have combined to buckle the track. The quality of the track was already suffering from ballast contamination, which would have weakened its resistance to lateral forces. Hot weather in the period leading up to the derailment, along with the trains travelling along the track, probably combined with maintenance activities to affect the concentrations of stress within the track, causing it to buckle.
As a result of the accident and the investigation, the Australian Rail Track Corporation (ARTC) has initiated several measures to address the problem. Maintenance staff have received additional training, while the track has been tested at 10 sites near the point of derailment. Meanwhile, the ARTC has implemented a ballast remediation program on the Melbourne-Sydney rail corridor.
The ATSB urges all track managers to take the factors of this accident into account when undertaking maintenance and reviewing the condition of their tracks.
Read the report: Derailment of freight train 3MC1, near Locksley, Victoria, on 12 February 2013