What does a "clear" signal mean for a locomotive engineer?

A "clear" signal primarily communicates to the locomotive engineer that the track ahead is unobstructed, allowing the train to proceed safely and at its authorized speed. This signal is vital for ensuring smooth operations, as it gives engineers the assurance to maintain momentum without the need for immediate caution or speed reductions. When a signal is clear, it implies that there are no hazards or upcoming signals requiring a halt or significant change in speed, enabling efficient train movement along the route.

In contrast, signals indicating a need to reduce speed, mandatory stops, or construction warnings would prompt the engineer to take specific actions that could interrupt the normal operation of the train. Therefore, a clear signal is essential in the chain of communication that governs train movements, ensuring safety and efficiency on the railway.