What should a vessel do when using a white light?

When a vessel displays a white light, it is primarily used to indicate that it is a power-driven vessel. This is in accordance with the navigation rules that govern vessel lights. A power-driven vessel must exhibit specific lights to be easily identified by others on the water, and a white light is an essential component of those signal lights.

The visibility of the white light helps ensure that other vessels can quickly determine the nature and status of the vessel, thereby promoting safety and preventing collisions. For instance, a white light is typically shown at the stern and can also be atop the mast to denote a vessel under power.

In terms of signaling, while a white light can indicate a range of statuses depending on its configuration, it does not imply that the vessel is aground, signaling, or is a sailboat, as these situations are designated by different lighting configurations or colors. Thus, the role of a white light directly pertains to a vessel's identification as a power-driven craft, ensuring proper communication and understanding among all mariners.