If a vessel not under command is making way, what additional lights will it exhibit?

A vessel not under command, which is defined as one that is unable to maneuver as required by the Navigation Rules, must display specific lights to indicate its status. When such a vessel is making way through the water, it is required to exhibit sidelights and a stern light.

The reason for this is that sidelights help indicate the direction the vessel is facing, with the green light indicating the starboard side and the red light indicating the port side. The stern light, which is white, illuminates the rear of the vessel, enhancing visibility to other vessels approaching from behind. Together, these lights serve to communicate the vessel's status and direction to other mariners, thus promoting safety on the water.

Flashing white lights, day shape signals, or just sidelights alone would not provide the complete information required for a vessel making way that is also not under command. Therefore, displaying sidelights along with a stern light is the appropriate and necessary way for such vessels to signal their presence and status on the water.