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Date reported
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Concern summary

The concern related to overloaded trains de-rating while going through tunnels on very hot days. This results in the train crew having to use respirators to evacuate the tunnel.

Reporter's deidentified concern

[Operator] are overloading coal trains, which in turn causes the trains to go too slow, the locomotives overheat and de-rate on entry into [location] tunnel and eventually lose traction and fail. Train Crew have to evacuate the tunnel using respirators and this is becoming a common occurrence during hot weather.

[Operator] are running trains that are 2 x [type] class locomotives and 88 wagons for 10,560 tonnes, these trains are entering the tunnel at 13 kilometres per hour and are choking on their own heat and emissions. When a locomotive enters a tunnel it starves for oxygen and the fuel mixture runs very rich causing the locomotive to blow huge amounts of black smoke.

In the last two weeks, three trains have failed in [location 1] tunnel due to overheating, all three crews had to evacuate the tunnel using respirators. The train and rescue crews all escaped without injury.

This is not a coincidence, three hot days, three tunnel failures.

[Operator] needs to reduce the size of their coal trains before there is a fatality in this tunnel.

Reporter comment: My main concern is, [Operator] are putting train crews at unnecessary risk due to the overloading of the locomotives.

Named party's response

Train Loading Conformance:
None of the specific instances cited were overloaded when compared to our operationally approved processes and procedures underpinned by our internal load table for [Region 1 – containing location 1] operations. The first two of the three services were, in fact, short loaded to 86 wagons, in accordance with our local operational procedures, due to the high ambient temperature, on those days.

Train Operating Conformance:
In all three cited instances the second locomotives suffered a critical failure in the engine cooling system which lead to the engine, in the second locomotive, shutting down (low water) and the consist coming to rest inside the tunnel. With only one locomotive active, only 6 of the 12 traction motors were available and the train came to a stand.

The cooling system failures coincided with the high engine load due to the bank and the relatively high ambient temperatures, up to a maximum daily temperature recorded on the days of interest.

In each of the incidents, the high load on the cooling system resulted in a catastrophic cooling system failure as opposed to derating which is where a locomotive reduces its output to protect itself from further damage.

Train Failure Response Conformance:
We recognise that a train coming to a stand in the [location 1] Tunnel is a credible and foreseeable risk and had taken reasonable steps to minimise the identified risk to our employees. On all three occasions, for each train, the evacuation and train recovery procedures were complied with and there were no injuries reported by the train crew involved. We acknowledge that this undesired event can affect our employees for which prompt post incident support is made available and provided as per the our Employee Assistance Program.

Regulator's response

Prior to receiving the REPCON Report, the ONRSR was contacted by an [operator] employee who expressed concerns similar to what is documented within the mentioned REPCON Report.

As such, the ONRSR had commenced enquiries accordingly. Initial enquiries included (but not limited too);

  • verifying the incidents had occurred
  • ascertaining why the incidents had not been reported to ONRSR
  • ensuring future incident/s of this type are reported to ONRSR and
  • what action(s) were or had been taken to reduce the likelihood of a reoccurrence.

In summary, the ONRSR believes the incidents are of a safety concern. The ONRSR will be conducting further enquiries with the operator, which will include monitoring the movement of trains through the [location 1] tunnel for any further instances of trains failing to lift loads within the tunnel and the crew evacuating using respirators.

Additionally, the ONRSR is of the belief that the reported safety concerns warrants further action from the rail infrastructure manager. As such, further enquiries will be conducted regarding the matters at hand.