At about 1654 on 15 January 2014, a Sydney Trains service made up of two four-carriage Tangara electric multiple units, entered the underground section of the Eastern Suburbs Line under Sydney city centre heading towards its destination, Bondi Junction. Some smoke and a burning smell were apparent emanating from the train at Central station and at all subsequent stations to Bondi Junction. A number of station and train crewing staff were aware of this but the condition was not reported to the appropriate network control officer as required under Sydney Trains’ Network Rules and Procedures.
The train terminated at Bondi Junction where a different driver took control of the train before it departed on its return journey. It then travelled to the next station, Edgecliff. Shortly after departure from Edgecliff, at 1726, the lead bogie of the third carriage derailed due to a broken axle on the leading bogie of the third carriage. A piece of angle iron that became dislodged from the track infrastructure penetrated the floor of the third carriage and entered a space occupied by passengers.
The ATSB found that an unauthorised, non-standard repair had been carried out on the axle in December 1998 or January 1999 which introduced stress initiators, causing a crack to develop which over time propagated to the extent that the axle failed in service.
It was also determined that a number of organisational factors contributed to the incident with examples of poor communication and lack of adherence to procedures and reporting lines leading to the train continuing in service and subsequently derailing.
Sydney Trains and their maintenance contractors undertook an archival document search and determined that seven axles, including the failed axle, had been repaired in the same way. All were immediately removed from service.
Sydney Trains, after conducting its own investigation into the circumstances surrounding the incident, produced a number of safety recommendations which the organisation is considering through its own Safety Action Management procedures.
Rail operators should ensure that maintenance procedures are followed and that non-standard repairs comply strictly with an approved variation and do not introduce new risks to operations.
Also, rail operators should review their internal training and communication pathways both within and between business units / operational areas to ensure that critical communication can occur in line with best current Rail Resource Management principle.