What should a train operator do upon seeing a signal aspect that means "stop and stay"?

The appropriate action for a train operator upon encountering a signal aspect indicating "stop and stay" is to stop and remain in place. This action is essential for safety and operational efficiency. When a train operator sees this signal, it communicates that there is an immediate requirement to halt all movements.

Stopping and staying in place ensures that the train does not proceed into potentially hazardous situations, such as entering a blocked section of track or approaching a train on the same line that is not at a signal aspect allowing movement. Remaining stationary allows the operator to assess the situation further, wait for additional instructions, or clear guidance from signaling personnel.

Continuing at full speed, reducing speed while proceeding with caution, or stopping and preparing to move again would compromise safety and could lead to serious incidents on the track. The signal system is designed to manage train movements precisely, and adherence to stop and stay commands is critical to maintaining safe operations.