A vessel that is anchored and is at least 50 meters long must display which lights?

• A. White lights forward only
• B. White lights aft only
• C. White lights forward and aft
• D. No lights

Answer: (C)

When a vessel is at anchor, its lights communicate that it is stationary to other mariners. For a vessel that is 50 meters or longer, the regulations require two all-round white lights arranged in a vertical line: one forward toward the bow and one aft toward the stern. This setup makes the anchored vessel conspicuous from any direction and lets other ships determine its position and orientation, helping to prevent collisions, especially at night or in restricted visibility. A single white light or no lights does not satisfy the rule for a vessel of this length, which is why showing white lights forward and aft is the correct requirement.