A green over green signal indicates what for the train?

A green over green signal indicates that the train can proceed on the main route with the assurance that the next signal is also clear. This is an important aspect of signal systems, as it provides the engineer with the necessary information to continue their journey without the need for immediate caution or stops. The clear indication means that the track ahead is safely available for travel, helping to maintain the flow of train operations and reducing the potential for delays or accidents.

Understanding this signal helps train operators to effectively gauge their speed and manage their approach to subsequent signals, ensuring they can maintain efficiency while also adhering to safety regulations.