199703 – Duffy – Signalling Changes for Operational Improvements – Dynamic Speed Indicators

Because Queensland Rail operates trains over the north coast line and coal lines which have vastly different performance characteristics, the signalling system can, at best, only hope to be a compromise between operational efficiency, cost and inherent safety. To date, QR has achieved a good balance in relation to these competing factors.

However the need to continue to operate a mixed train service and provide for 80 kph coal trains, 100 kph freight, 160 kph tilt train, IMU’s etc on the NCL, whilst maximising the commercial return from infrastructure and rollingstock, has highlighted the need to review the appropriateness of some signalling information displayed to drivers and to consider the current signalling constraints impacting on the efficient and effective operation of trains. Two signalling issues which impact on operational efficiency and which have the potential to become significant impediments to the effective operation of trains are:
1. The need to provide train crews with more specific signalling information, at the approach signal position, to facilitate improved train handling.
2. The need to review the maximum speed of trains on passing home signals under simultaneous entry situations.

Higher speed train operations are being catered for by the progressive installation of higher speed turnouts. However the operational benefits of some of these turnouts could not be fully realised because of limitations in application of QR’s existing signalling design philosophy and practice. This invariably meant that the higher performance trains suffered a penalty under certain signalling conditions. Such situations were increasing in number. The impact of the signalling system was already being felt adversely in the operation of coal, freight and passenger services on the NCL.

A need was identified by the Business Groups to improve train operations efficiencies and to display clear and consistent signalling and route information to drivers.

As a result, discussion papers were produced by SAOS and a series of signalling philosophy workshops were conducted to determine actions that could be taken to improve the signalling system operation.

The workshops were made up of Train Operations staff, Drivers, and Signal Maintenance Staff from the Business Groups and staff from the Safeworking and SAOS Sections.

This paper therefore attempts to address the issues associated with the introduction of the dynamic speed indicator.