At night, what type of vessel would display yellow over yellow lights?

Displaying yellow over yellow lights at night indicates a vessel that is engaged in operations that warrant the use of such signaling. In this case, a tugboat that is pushing a barge ahead is the correct identification for exhibiting yellow over yellow lights. This specific light configuration is utilized to signify the presence of a towing vessel engaged in pushing ahead or when towing alongside.

The importance of these lights comes from the need to communicate the specific type of operation and of the vessel to other mariners, ensuring safety and proper navigation. The yellow light signals clearly indicate that the vessel is not simply navigating the waters but is actively engaged in towing, which has distinct navigational considerations, especially in congested waterways or at night.

Other vessel classifications like fishing vessels, power-driven vessels, and sailing vessels utilize different light configurations in accordance with the International Regulations for Preventing Collisions at Sea (COLREGs) and the U.S. Coast Guard regulations, thereby making them distinguishable from a tug pushing a barge. Understanding these signals is crucial for safe maritime navigation.