Editing Navigation light (section)

{{Short description|Lights on a vessel, aircraft or spacecraft giving information on its position, heading, and status}}
{{redirect|Position light|the railroad signals|North American railroad signals#Position light signals}}
{{Use British English|date=July 2022}}
[[File:Propmec50.PNG|right|thumb|Basic lighting configuration. 2, a vessel facing directly towards observer; 4, vessel facing away from the observer]]
[[File:Raptors refuel 140926-F-ML224-004.jpg|thumb|upright|Red and green navigation lights on an [[Lockheed Martin F-22 Raptor|F-22 Raptor]]]]
[[File:Dragon approaches the ISS (32238998824).jpg|thumb|Red and green bottom navigation lights on [[SpaceX Dragon]]]]
A '''navigation light''', also known as a running or position light, is a source of illumination on a [[watercraft]], [[aircraft]] or [[spacecraft]], meant to give information on the craft's position, [[Direction (geometry)|heading]], or status.<ref>{{cite book |title=A Dictionary of Aviation |first=David W. |last=Wragg |isbn=9780850451634 |edition=first |publisher=Osprey |year=1973 |page=200}}</ref> Some navigation lights are colour-coded red and green to aid traffic control by identifying the craft's orientation. Their placement is mandated by international conventions or civil authorities such as the [[International Maritime Organization]] (IMO).

A common misconception is that marine or aircraft navigation lights indicate which of two approaching vessels has the "right of way" as in [[traffic#Passage Priority (right of way)|ground traffic]]; this is never true. However, the red and green colours are chosen to indicate which vessel has the duty to "give way" or "stand on" (obligation to hold course and speed). Consistent with the ground traffic convention, the rightmost of the two vehicles is usually given stand-on status and the leftmost must give way. Therefore a red light is used on the ([[port and starboard|left (port)]]) side to indicate "you must give way"; and a green light on the ([[port and starboard|right (starboard)]]) side indicates "I will give way; you must stand on". In case of two power-driven vessels approaching head-on, both are required to give way.