While the design of the on-load release system allowed the reset position of the hook to be visually confirmed, it did not allow for visual confirmation that the release segment and mechanism had been correctly reset. Consequently, the hook device could appear to be properly reset when it was not.
The manufacturer’s calculations did not take into account the shock load imposed on the simulation wires or the lifeboat and launching frame mounting points.
An equivalent, alternative arrangement to the safety pin had not been provided to prevent inadvertent tripping of the freefall lifeboat’s on-load release during routine operations, such as inspections and maintenance.
The design of the VCA type 37 mixed gauge turnouts (MYD882 and MYD887) was such that they were not suitable for use by rolling stock with a 127 mm rimmed wheel.
V/Line’s processes for responding to the report by the driver of train ST21 did not limit or prevent the subsequent movement of train ST24 before checks had been carried out to identify and assess any potential track and/or rolling stock issue(s).
Contract documentation and specifications within the Services and Supply Umbrella Agreement were generic and did not adequately specify the intended purpose of the type 37 turnout.
Inherent to the design of many dual gauge turnouts, is a region of reduced wheel rim contact on the broad gauge switch blade (rail head) through the transfer area. In circumstances where the switch blade is insufficiently restrained, and where the passing train has a narrow (127 mm) wheel rim width, there is an increased risk of derailment.
The physical testing and commissioning regime for the VCA type 37 turnout did not require the use of standard gauge trains with 127 mm rimmed wheels.
The VCA type 37 turnout design and V/Line’s provisional type approval process did not fully identify the subtle design changes inherent with the VCA type 37 turnout in determining testing, commissioning and validation needs.
The method of constructing crossings at unsealed roads heightened the potential for corrosion and track degradation and limited the opportunity for effective visual inspection. The network standard for crossing construction did not directly address the particular challenges of unsealed roads.
The track inspection regime did not identify the deteriorated rail condition at the O’Tooles Road level crossing. The regime placed an over-reliance on ultrasonic testing and did not include sufficient supplementary systems for monitoring the condition of buried track at unsealed level crossings.
The ultrasonic testing regime was not effective in consistently identifying corrosion and wasting of the rail web at unsealed level crossings.
GWA had no documented system in place to assess the suitability of second-hand components for re-use.
When travelling at speeds near 90 km/h on track having particular track irregularities, the WOE class wagons appear to be susceptible to harmonic oscillations of sufficient magnitude to produce wheel unloading, flange climb and derailment.
The frequency of driver reporting and locomotive cab rides by track inspectors had been insufficient for identifying rough track through the derailment site.
After re-railing the track, permitted train speed was increased without due consideration of the effects of cyclic track irregularities on the dynamic performance of the WOE class wagon.
The loss of brake pipe integrity during the derailment event did not result in the train brakes automatically activating.
A register for recording ‘special locations’ in accordance with the ARTC Engineering (Track & Civil) Code of Practice - Section 10 – Flooding, had not been established to manage track infrastructure prone to flood damage.
The ARTC’s processes for developing and implementing changes to operational procedures as a result of incident investigation findings were ineffective at mitigating the risk of future similar incidents.
The ARTC did not have a comprehensive system in place to identify and actively manage risks associated with severe weather events that were likely to affect the safety of their rail network.
