At night, what signal does a vessel towing astern display?

A vessel that is towing astern displays two vertical red lights when viewed at night. This indicates to other vessels that it is engaged in a towing operation. The use of red lights serves a dual purpose in ensuring the safety and awareness of nearby vessels, indicating that the towed vessel may be restricted in its ability to navigate and maneuver.

In nighttime navigation, the visibility of these lights is crucial for maintaining safety on the water, as they help prevent collisions and allow other vessels to understand the nature of the towing operation. The presence of two vertical red lights creates a distinct signal that is easily recognized by other mariners, underlining the importance of proper signaling while on the water.

Understanding this signaling is especially vital during the night when visibility is reduced and other forms of communication are limited. It ensures that the vessels around are aware of the towing situation, which can significantly impact their navigation choices.