Editing Navigation light (section)

===Basic lighting===
[[Watercraft]] navigation lights must permit other vessels to determine the type and relative angle of a vessel, and thus decide if there is a danger of collision. In general, sailing vessels are required to carry a '''green''' light that shines from dead ahead to 2 [[Points of the compass|points]] ({{frac|22|1|2}}°) abaft<ref group="note">[[wiktionary:abaft|abaft]]: to the rear/closer to stern/'aft'</ref> the beam on the [[starboard]] side (the right side from the perspective of someone on board facing forward), a '''red''' light from dead ahead to two points abaft the beam on the port side (left side) and a '''white''' light that shines from astern to two points abaft the beam on both sides. Power driven vessels in addition  to these lights, must carry either one or two (depending on length) white masthead lights that shine from ahead to two points abaft the beam on both sides. If two masthead lights are carried then the aft one must be higher than the forward one.

Small power-driven vessels (under {{convert|12|m}}) may carry a single all-round white light in place of the two or three white lights carried by larger vessels, they must also carry red and green navigation lights.  Vessels under {{convert|7|m}} with a maximum speed of less than {{convert|7|kn}} are not required to carry navigation lights, but must be capable of showing a white light.<ref>{{Cite web |title=Amalgamated International & U.S. Inland Navigation Rules: Part C - Lights and Shapes |url=https://www.navcen.uscg.gov/navigation-rules-amalgamated |access-date=July 18, 2022 |website=United States Coast Guard Navigation Center}}</ref> Hovercraft at all times and some boats operating in crowded areas may also carry a yellow flashing beacon for added visibility during day or night.