If a train stops less than one engine length beyond an interlocking signal, what must it do?

When a train stops less than one engine length beyond an interlocking signal, it is crucial for safety and adherence to operating protocols that the crew must obtain permission from the Dispatcher before proceeding. This action is necessary because stopping in this position indicates that the train may still be within the limits of the interlocking signal's jurisdiction and could potentially affect the operation of other trains or the signal system itself.

By ensuring that permission is secured from the Dispatcher, the train crew confirms that it is safe to proceed and that all other relevant factors, including the status of the track and the signal information, have been properly communicated. This protocol reinforces the operational safety and integrity of the railway network, thereby preventing accidents and ensuring efficient train movements.