005/15

Status
Open
Recommendation Date
Recipient Name
NZTA
Text
Rail Standards for New Trains

The National Rail System Standards (6) (Engineering and Interoperability) is the only standard within the National Rail System set that defines braking performance. However, it does not address the performance in low adhesion conditions of modern metropolitan passenger trains that are fitted with computer controlled brake and wheel slide protection systems. The current National Rail System Standard (6) does not require any more from a braking system than for a train to be able to stop within a specified distance in dry conditions.

The regulator for the country of operation or the purchaser may define what adhesion conditions might be encountered on a rail network and what level of braking performance is expected from a new train and what standards the train is to be tested to for compliance. This is also the stage in commissioning a new train, when the interaction between all of the brake systems is adjusted to achieve the optimum overall brake performance. The Rail Safety and Standards Board in UK have produced a Guidance Note (GM/GN2695) to achieve this purpose in the UK but nothing similar exists for New Zealand.

The Matangi train brake systems were tested for compliance and proper operation, but they were not tested and adjusted for optimum brake performance in low adhesion conditions.

In Wellington, where new trains were commissioned into service with computer controlled braking and wheel slide protection systems, but that the complete train braking systems were not optimised to achieve the most effective brake performance in low adhesion conditions. The Commission considers that the occurrences in Wellington may be repeated unless the National Rail System standards are revised.

As a minimum the Commission considers that the National Rail System standards should call upon appropriate international standards to formalise new train type testing and ensure that train braking systems are tested in low adhesion conditions and optimised for the train.

The Commission recommends that the Chief Executive of the New Zealand Transport Agency require a full review of the National Rail System standards, and in particular standard No. 6, to ensure that low adhesion braking requirements are defined in the standards and made applicable for all trains intended to operate on the National Rail System.
Related Investigation(s)