Rule 251 Territory: When track is signaled in only one direction, signal indication will be the authority for trains to operate with the current of traffic.

• A. To operate with the current of traffic.
• B. To operate in either direction on the same track.
• C. To stop and proceed only with permission.
• D. To proceed only with a Form D.

Answer: (A)

When track is signaled for only one direction, the signal indication itself is the authority to move, and trains must follow that direction—the current of traffic. In this one-way signaling setup, you proceed in the direction shown by the signal and do not move against the flow. The other options imply movement in a direction not authorized by the single-direction signal or require extra permissions that aren’t needed when the signal governs movement. So the correct idea is that you operate with the current of traffic.