At night, you sight navigation lights; which configuration would indicate a tug with a tow alongside?

At night, you sight navigation lights; which configuration would indicate a tug with a tow alongside?

• A. A tug with a tow alongside
• B. A sailing vessel with side lights
• C. A power-driven vessel not under command
• D. A vessel at anchor

Answer: (A)

When a vessel is towing another, other ships must be able to recognize the towing arrangement at night. The telltale signal is an extra white light—the towing light—mounted on the towing vessel in addition to its normal navigation lights. This white towing light indicates to others that a tow is in progress and that the tug is not free to maneuver as a standalone vessel. So the configuration that best indicates a tug with a tow alongside is the tug displaying its usual lights plus the additional towing light. The other options portray lights for vessels not engaged in towing (a sailing vessel’s sidelight pattern, a power-driven vessel not under command, or a vessel at anchor) and do not indicate towing.

When a vessel is towing another, other ships must be able to recognize the towing arrangement at night. The telltale signal is an extra white light—the towing light—mounted on the towing vessel in addition to its normal navigation lights. This white towing light indicates to others that a tow is in progress and that the tug is not free to maneuver as a standalone vessel.

So the configuration that best indicates a tug with a tow alongside is the tug displaying its usual lights plus the additional towing light. The other options portray lights for vessels not engaged in towing (a sailing vessel’s sidelight pattern, a power-driven vessel not under command, or a vessel at anchor) and do not indicate towing.