What does a red signal aspect indicate and what must the train do?

• A. The signal indicates the track is clear; continue normally.
• B. Stop; the train must not pass the signal and must proceed only when the signal shows a proceed aspect and clearance is given.
• C. Proceed at reduced speed after confirming with the control center.
• D. The signal indicates track maintenance; proceed with caution.

Answer: (B)

Red signal aspect tells the train to stop. It indicates that the route ahead is not authorized for movement, and the train must come to a full stop before the signal. The train crew must not pass the signal in red. Movement can only resume once the signal changes to a proceed aspect and the dispatcher or control center has granted clearance, confirming the track is clear and any required speed or authority conditions are in place. This ensures the train only proceeds when it is safe and authorized to do so.