18 July 2017
On 21 April 2016, at about 1115, train 3MP5 (travelling from Melbourne to Perth) derailed while traversing the eastern points at Rawlinna. The points failed to restore to the normal position after the last train departed the loop line, leaving the points in an unsafe open position. The colour light point indicator system worked as designed by displaying a red indication when the points were unable to be detected and locked in a safe position.
There were minor injuries sustained by the crew. About 200 m of track infrastructure was damaged, and the main line between Adelaide and Perth was blocked until 1351 on 25 April 2016.
The ATSB found the driver’s expectation that the system was likely set for the main line contributed to train 3MP5 travelling at a speed where it could not be stopped before the open points. Additionally, it was likely a common practice for drivers to approach crossing locations without slowing when authorised for the main line. Compounding this was the points enhancer sighting distance being less than the effective braking distance of trains travelling at line speed, thereby increasing the risk of overrun if not displaying a green aspect.
The ATSB also found that the crew van did not meet the requirements of AS 7522-2012 - Railway Rolling Stock Access and Egress, since the occupant could not access any escape paths without external assistance and additional equipment.
Pacific National have reviewed operational instructions, audited enhancer sighting distances between Cook and Kalgoorlie, and reviewed emergency egress arrangements. The Office of the National Rail Safety Regulator will look further into the possibility of prescription glasses with progressive lenses altering the perception of signal colours.
The common practice of approaching safety critical zones at higher speed
probably affects multiple operators. The effective sighting distance of safety
critical locations (enhancers, targets, etc) being less than the effective
braking distance of trains represents a physical gap or limitation of the
system. This limitation places more reliance on procedures to cover the gap.
Although the Australian Rail Track Corporation and Pacific National have
procedures in place, not all operators have the same requirements. Other operators
may instead rely on one layer of procedural protection provided by the track
manager, increasing the likelihood of an occurrence.
Investigation report: Derailment of train 3MP5 at Rawlinna, WA on 21 April 2016