What is the minimum length of an anchored vessel which is required to show a white light both forward and aft?

The requirement for an anchored vessel to display white lights both forward and aft is outlined in the International Regulations for Preventing Collisions at Sea (COLREGs). Specifically, vessels that are anchored and are 50 meters or more in length must show these lights to enhance visibility and provide a reference for other vessels nearby, ensuring safe navigation.

The purpose of displaying white lights at both ends is to indicate the presence of a vessel at anchor, especially for those navigating in the vicinity. This visibility is crucial, particularly in low-light conditions or when visibility is poor, as it helps prevent collisions.

For vessels under 50 meters in length, the regulation allows for more leniency, where a single white light can suffice. Therefore, vessels that meet the specified length requirement have to adhere to displaying both forward and aft white lights as part of the safety measures in maritime navigation.