An anchor light is a white navigation light that indicates a stationary vessel at anchor. This light is mandatory under international maritime regulations and ensures that other vessels can see the anchored vessel in time to avoid collision.
1. Features of an anchor light
✅ White light → Burns continuously and is visible all around (360°) .
✅ Placed at the highest point of the ship → Usually on the mast or an elevated position.
✅ Mandatory in poor visibility and at night → Must burn between sunset and sunrise .
✅ Different requirements depending on vessel size → Rules differ for small boats, sailing ships and large vessels .
2. When is an anchor light mandatory?
According to the International Regulations for Preventing Collisions at Sea (COLREGS), an anchor light is required in the following situations:
| Ship length | Anchor light obligation |
|---|---|
| < 7 meters (23 ft) | Only mandatory in poor visibility or busy areas. |
| 7 - 50 meters (23 - 164 ft) | One white all-round light on the mast. |
| > 50 meters (164+ ft) | One white light on the mast + additional deck lighting to make the hull visible. |
📌 Sailing boats without a motor → Must also carry an anchor light.
3. Difference between an anchor light and other navigation lights
| Light type | Goal | Colour | Placement |
|---|---|---|---|
| Anchor light | Shows an anchored ship | White (360°) | Highest point of the ship |
| Masthead Light | Shows a sailing ship | White (shining forward) | Mast or bow |
| Port light | Indicates left side of the ship | Red | Left side of the bow |
| Starboard light | Indicates right side of the ship | Green | Right side of the bow |
| Stern Light | Shows the rear of a ship | White | Rear of the ship |
4. What requirements should an anchor light meet?
✔ Visibility → Must be visible for at least 2 miles .
✔ 360° all-round illumination → Must be visible from all sides .
✔ Automatic activation → Many modern anchor lights switch on automatically at dusk.
✔ Energy efficient → LED versions are increasingly used due to their low energy consumption.
5. Commonly used anchor lights
🔹 LED anchor lights → Low power consumption, long lifespan.
🔹 Portable anchor lights → For small boats and sailboats without a fixed installation.
🔹 Solar-powered anchor lights → Self-sufficient and ideal for long anchorages.
🔹 12V/24V anchor lights → Common for motorboats and yachts.
💡 In short:
An anchor light is a white, 360° all-round light , mandatory for vessels at anchor to ensure visibility and prevent collisions. Regulations vary depending on vessel size , and modern versions often use LED or solar power .