Investigators are still unsure how a 16-tonne steel coil fell from a train on the interstate network earlier this year near Winton, in northern Victoria, damaging track and a V/Line train which collided with the coil minutes later.
The Australian Transport Safety Bureau this week revealed its preliminary findings into the March incident, which involved a Pacific National service delivering steel from Port Kembla to Melbourne Freight Terminal.
A steel coil which fell from the train damaged trailing wagons and the track, before coming to a rest between, and obstructing tracks in both directions.
The driver of a V/Line passenger service, approaching the incident site from the opposite direction about 10 minutes later, saw the coil and applied the emergency brake, but collided with the tail of the coil “at a speed above 100km/h” before coming to a halt, according to the Bureau’s report.
The V/Line train fortunately did not derail, and damage was found to be superficial. No injuries were reported. The trailing wagons of the freight train were damaged by the coil to varying extents, and the track was substantially damaged at the incident site.
In its preliminary report, published on November 19, the ATSB explains Bluescope Steel had loaded a pair of jumbo coils onto a wagon on March 27.
That wagon was inspected by PN terminal operators on March 28 and moved to the South Yard at Port Kembla. On March 29 it was marshalled as the 35th wagon of PN freight service 6WM2.
The train was made up of four locomotives hauling 75 wagons, making it 1,275.3 metres long. It left Port Kembla at 11:54pm on March 29.
Crews changed over at Chullora at 3am on March 30, then another crew change occurred at Junee the same day at 10:55am. Both times, disembarking crew members reported the train was running well and conducted a roll-by inspection of the departing train, with no issues reported, the ATSB says.
When the train passed Wangaratta Station, it was captured on CCTV.
“Closed circuit television footage captured from a platform at Wangaratta Station at about 1427 identified that all jumbo coils on train 6WM2 were present and not grossly out of place,” the ATSB says.
“The quality of the footage was not sufficient for the ATSB to determine whether the unitising straps were still attached to the coils [on the wagon in question].”
The coil fell from the train at around 2:40pm, while the train was travelling at roughly 76km/h.
The steel coil, comprising a wound sheet of 3.2mm-gauge steel, weighed 16.04 tonnes, was 1.93 metres in diameter and 0.8 metres wide.
It had been loaded into the trailing cradle of the wagon, with another coil loaded into the leading cradle of the wagon. It was unitised with steel strapping – two circumferential and two radial straps – according to the ATSB.
No clear reason has so far been identified for the coil coming free.
“Track grade leading to the incident site was relatively flat and the driver had been maintaining moderate traction power (throttle between notches 2-5) for approximately 2 minutes prior to the loss of the coil,” the report states.
“The drivers of 6WM2 reported nothing remarkable about the train’s behaviour at the incident location and were not aware that the coil had fallen off at the time.”
Inspections of the wagon which had carried the coil found the rubber mat was dislodged from one face of that coil’s cradle, and found witness marks on the exposed metal surface of the cradle. There was also a break found in the wagon frame, under the other cradle.
With its preliminary report now complete, the ATSB will move on to examining the loading, load restraint and examination processes with respect to jumbo coil wagons.
It will also review the frequency and mechanisms of historical occurrences of jumbo coil load shift, examine the possible dynamic forces acting upon the wagon during the incident, analyse the effect of wagon condition on the incident, and analyse track conditions, both historically and on the day in question.
The Bureau expects to conclude its investigation in the second quarter of 2019.