Rules of the Road · Light Definitions & Visibility

According to the COLREGS, what is the minimum required visibility range for a masthead light on a vessel 50 meters or more in length?

Explanation

Rule 22(a) requires masthead lights on vessels 50 meters or more in length to be visible at a minimum range of 6 miles. Sidelights on the same vessels require 3 miles, and the sternlight requires 3 miles — masthead lights have the greatest range requirement.

Authority: 72 COLREGS Rule 22(a)

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