What is the purpose of the tricolor light on a sailboat?

The tricolor light is specifically designed for use on sailboats, particularly when they are under sail. It serves as a combination of the three navigation lights – red, green, and white – typically used to indicate the sailboat's heading and to show its visibility to other vessels. When a sailboat is under sail and not using its motor, the tricolor light is mounted at the masthead and displays a green light to starboard (right side), a red light to port (left side), and a white light to indicate the stern (back). This setup allows for 360-degree visibility, which is crucial for safety in maritime navigation, especially at night or in low visibility conditions.

When the tricolor light is on, it communicates to other vessels that the sailboat is under sail, which is essential for determining right-of-way and for avoiding collisions. Understanding the purpose and function of the tricolor light reinforces its importance in maintaining safe navigation practices on the water.