Derailment of freight train 6MB2, at Tottenham, Victoria, on 30 January 2009

Executive summary

At about 1515 on 30 January 2009, northbound freight train 6MB2, owned and operated by Pacific National, derailed near the beginning of a left-hand curve located near the 8.915 track km point in Tottenham, Victoria. In total, 8 wagons derailed and about 400 m of timber sleepered track was damaged. Damage to rolling stock was minimal and there were no injuries as a result of the occurrence.

At the time of the derailment, major infrastructure works between Melbourne and Sydney were being carried out to improve the general track condition and operating efficiency on the standard gauge rail corridor.

Train 6MB2 derailed as it passed over a section of mainline track in the Tottenham Yard precinct that contained a build up of longitudinal rail stress after three consecutive days of very high ambient temperatures. Due to the extreme weather conditions, the Australian Rail Track Corporation had implemented heat speed restrictions for train operators between Tottenham and Albury, restricting trains to speeds not greater than 60 km/h.

When train 6MB2 approached the left-hand curve near the Ashley Street Bridge, the train crew observed that a small lateral misalignment had developed in the track. During the passage of the train the dynamic movement of the rail vehicles added sufficient force to increase the size of the misalignment as the train passed over it. A container flat wagon (NQKY 34695L), 31st in the consist, was the first vehicle to derail and it was positioned near the rear of the train.

No evidence was found that defective rolling stock components had contributed to the derailment and minor damage to the rolling stock was sustained during the derailment sequence.

The investigation found that as part of the project works, the Tottenham standard gauge passing loop was converted for mainline operation on 28 July 2008. A safety issue was identified where this section of track was not tested after the conversion to mainline to determine if any residual stress was present in the rails and if any treatments were necessary to reduce the likelihood of track misalignments.

Other safety issues identified that creep monuments had not been installed at the east end of the curve near where train 6MB2 derailed and the rails had not been punch marked to allow track inspectors to detect rail creep. In addition, a record of two rail welds carried out at the 8.351 km point on the 30 January 2009 had not been documented for future reference. Attention to both of these items were specific requirements of the V/Line Infrastructure Civil Engineering Circular 3/87.

Following the derailment, the Australian Rail Track Corporation reconstructed this section of track and replaced the timber sleepers with concrete sleepers as part of the Tottenham to Dynon infrastructure track upgrade.