Passing a signal at danger under verbal authority with a failed track circuit
At 07:20, the driver of suburban train 2A16, six cars and about 420 passengers, is stopped at signal S3 showing danger. The signaller reports that track circuit 3A has failed and is not detecting trains. The signaller proposes to give verbal authority to pass S3 at danger and proceed to the next signal. Beyond S3 is a pedestrian foot crossing 400 m ahead with no barriers, then facing points 8A set normal, then a station platform 600 m beyond. Fog limits visibility to about 150 m. The driver can hear another train moving on the adjacent line. The signaller has not yet stated whether the section beyond the points is clear or whether a pilotman is required. The driver must decide what to confirm before moving and how to proceed.
1. What must the driver confirm with the signaller before accepting the verbal authority?
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The driver should confirm the exact limits of the authority: that it covers only the movement past S3 to the next signal or a named point, and whether the line beyond points 8A is clear. The driver should ask whether the points are set and locked normal and whether any other train is in the section. Because track circuit 3A has failed, the signaller cannot rely on train detection, so the driver must be told what protection exists for the foot crossing and the station area. The driver should also confirm whether a pilotman or route conductor is required and whether the authority is being recorded. The driver should not accept a vague instruction such as 'proceed past the red'; the authority must identify the signal, the extent, and any conditions, and the driver should repeat it back.
2. What speed and actions are appropriate once authority is given?
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The driver should pass S3 only after stopping, confirming the authority, and checking that the route ahead is set. With fog visibility of about 150 m, the train must be driven at a speed that allows it to stop within the distance seen to be clear, which is likely to be around 20 km/h or less. The driver should sound the horn before the foot crossing, watch for pedestrians, and be prepared to stop short of anyone on the crossing. Approaching points 8A, the driver should check the point indicators and proceed at caution. Approaching the station, the driver should be ready for passengers on the platform and should not accelerate simply because the signal has been passed; the failed track circuit means the normal protection is degraded, so defensive driving is required until the next signal or a clear section is reached.
3. Halfway to the next signal, S3 unexpectedly clears and the signaller calls to say the track circuit has restored. What should the driver do?
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The driver should not treat the clear aspect as permission to resume normal speed immediately. The verbal authority was issued because the signalling system was degraded, and the restoration may be transient. The driver should acknowledge the signaller's call, confirm whether the authority is now withdrawn or whether the movement should continue to the next signal, and continue at caution until the whole train is past the affected section. If the signaller withdraws the authority, the driver must follow the new instruction. The driver should record the time of restoration and the change in authority. The key judgement is that a signal changing to clear does not retrospectively prove the section was clear while the train was in it; caution should be maintained until the train is confirmed to be in a normally signalled area.