On 11 July 2014, train ST21, a scheduled XPT passenger service, was travelling from Sydney to Melbourne. At Broadmeadows station (about 18 km north of the Melbourne CBD), a pilot boarded the train for the final part of the journey into Southern Cross station. The pilot was required to provide route familiarisation training for XPT drivers who were operating over the newly commissioned section of dual gauge track leading into and out of the Southern Cross station.

At about 0738, train ST21 entered the dual gauge ‘up’ fly over track and passed over MYD882 (dual gauge ‘up’ turnout), which was part of the newly commissioned track. As the train traversed the turnout, it bounced heavily. The pilot described it as ‘a short sharp dip in the track, similar to a short deep bog hole (mud hole)’ and explained that if the train hadn’t kept rolling, he would have thought they had derailed. The pilot immediately rang Southern Cross number 1 signal box and reported the occurrence. Number 1 signal box advised that they would arrange for a track inspection. The train continued into Southern Cross, where it was fuelled and joined by passengers and new crew, in readiness for the return journey to Sydney as train ST24.

At about 0830, train ST24 departed Southern Cross and travelled along the dual gauge ‘down’ fly over track on its journey towards Sydney. As the train approached signal MYD987, the driver observed a clear medium speed with ‘S’ indication. To the driver, this meant that the route was correctly set and that the train could traverse MYD887 (dual gauge ‘down’ turnout) at up to 25 km/h. As the train traversed the turnout at about 20 km/h, the driver and pilot felt several large jolts, followed by a series of fault indications on the driver’s display screen as the train came to a standstill. The pilot then rang the train controller and advised that train ST24 had derailed on the fly over. When the site was secured, the driver walked back to inspect the extent of the damage. Recovery personnel arrived shortly thereafter and commenced disembarking passengers.

Investigators from the ATSB and the Chief Investigator Transport Safety (CITS) Victoria attended the site and began gathering/protecting perishable evidence, including site data, photographs, measurements, CTC data logs and train data logs.

The investigation is continuing and will include an examination of the following:

  • Design, quality control, commissioning and acceptance testing processes for dual gauge turnouts.
  • The process for identification and examination of potential infrastructure or rolling stock defects that may result in derailment, following reports of suspected infrastructure irregularities.