The ARTC Code of Practice does not clearly address the possibility that a series of track irregularities, even minor ones which do not exceed intervention limits, could cause an undesirable harmonic response in some rail vehicles.
The ARTC Code of Practice does not clearly address the possibility that a series of track irregularities, even minor ones which do not exceed intervention limits, could cause an undesirable harmonic response in some rail vehicles. The ATSB recommends that the ARTC should address this safety issue.
Australian Rail Track Corporation recognises the issue identified by the Australian Transport Safety Bureau investigation and is undertaking research to identify a sustainable and practical approach to address the issue.
Australian Rail Track Corporation accepts that the track maintenance standard as currently applied treats each identified track geometry deficiency as a separate entity and may not fully recognise that there may be rare but possible combinations of track geometry deficiencies and rail vehicle ride characteristics that can unite to initiate a derailment. The identified deficiency relates more the spacing of minor track geometry deficiencies in combination with rail vehicle characteristics including bogie spacing and type, wheel profile and load placement than the size of the individual geometry deficiencies.
Australian Rail Track Corporation has a robust electronic track geometry measuring system in place with significant data captured and processed to generate a Track Quality Index (TQI) for any given track section. Research undertaken to date indicates the problem is not unique to the NCoP applied by Australian Rail Track Corporation, a review indicates that other codes applied within Australia and overseas have yet to define a systemic and sustainable long term solution to the problem.
Australian Rail Track Corporation considers that the issue is worthy of further consideration and has established a project group to review current standards and practices including the concerns raised by Australian Transport Safety Bureau.
The ATSB is satisfied that the intended action by the ARTC would adequately address the safety issue.
