Concern regarding a signal failure

[Signal number] was unable to display a proceed aspect unless the train departed the platform against a stop aspect and engaged the track circuit further down the line.

• The signal was operating as designed, that is, approach operated. Although not operationally beneficial, the design was not unsafe.
• The design issue was associated with turnback moves from platform 1 at [Location] station and not for through moves or turnback moves from platform 2.

When the defect was uncovered in the morning peak, signallers asked drivers to depart platform 1 [Location] and wait for the signal to display a proceed aspect. This breaches [Operator]'s platform departure procedures and risks a SPAD event for a home signal that protects a level crossing and points.

• Once detected, a review of the design and its functioning resulted in understanding that for a departing train to obtain a proceed aspect, the signal was required to be approached and the train occupy track section [number].
• Track section [number] is 30 m in length (35 m used as distance from stop mark to signal plus stopping tolerance on platform) 
  • maximum speed attainable within 35 m from a standing start (0 km/h) is 33.1 km/h
  • stopping distance for a [train type] travelling at 34 km/h is 53 m
  • on occupation of track section [number], level crossing commences activation and is completely closed in approximately 20 seconds.
• To ensure the movement of the train had appropriate controls in place, drivers were advised to activate ‘[mode 1]’ on the [train type] which has a maximum speed of 15 km/h.
• The distances of the platform, signal and level crossing are: 
  • Distance between platform stop mark and signal = 33 m 
    • Compliant signal sighting provided.
  • Distance between signal and level crossing = 72 m. 
    • A [train type] operating at 15 km/h would require 15 m to stop if passing signal [signal number] at stop.
    • Maximum speed attainable within 35 m from a standing start (0 km/h) is 33.1 km/h (distance between stop mark plus stopping tolerance and [signal number] signal)
    • Stopping distance for a [train type] travelling at 34 km/h is 53 m
    • Movement of the [train type] in [mode 1] or [mode 2] towards the signal at stop would not result in an unsafe situation

The reporter states that [train type] require more than 50% traction effort to move, and that slow manoeuvring of this train is difficult. Asking a driver to depart against a stop aspect is completely inappropriate considering the close proximity of the home signal to the platform.

Refer above to distances between the platform stop mark, signal and level crossing as well as operational performance of a [train type] in [mode 1] and [mode 2] including braking distance.

The reporter advises that [lead] drivers objected to the procedure, advising network control it was unsafe, however [Operator] persisted with the interim fix. It wasn't until a Health and Safety representative intervened at approximately [time] that [Operator] reconsidered the high-risk manoeuvres being conducted by drivers under the instruction of signallers.

At no point was the movement of trains considered high risk. [Operator]’s risk management process requires that where risks associated with a task are unable to be effectively managed, the task should not proceed. Adequate controls were identified and implemented to mitigate any risks associated with the movement of a [train type] from platform 1 at [Location] towards signal [signal number] and subsequently the level crossing beyond the signal.

Further to the engineering controls associated with [train type] [mode 1] and fitted train stops, signallers started routing as many trains as they could to platform 2 rather than platform 1 to reduce the frequency of having to move up toward the signal.

All the controls implemented remained in place until a software fix was able to be implemented to remove the approach activation functioning of the signal. 

The reporter acknowledges that [Operator] acted quickly to rectify the software issue and the signal is now functioning as intended. However, the reporter would like assurances from [Operator] that this incident is/will be reviewed, and that procedures will be implemented to ensure that a signal failure in the future will not result in drivers being directed to perform unsafe manoeuvres.

The identified issue has been recorded in [program] (reference number provided) and is currently being reviewed in accordance with [Operator]’s [incident management system] procedure [number] and investigation management procedure [number].

Primarily, the reporter states that instructing train drivers to start against a stop should not be a mitigation for dealing with signal irregularities and it is imperative that train control take advice from drivers/[lead] drivers if they are reporting unsafe operations. Secondly, the reporter believes that procedures need to be strictly adhered to during operational failures and that the appropriate authority should have been issued to pass the signal at stop or other operational solutions considered, that is shunt and redocks to avoid SPAD/operational incidents.

Appropriate authority (for example a [directive]) would only be required if drivers were required to pass the signal while at stop if the signal was defective. The signal was not defective but operating as approach activated.