What is the purpose of position lights on aircraft?

The purpose of position lights on aircraft is to indicate the aircraft's relative position to others in the sky, which is critical for ensuring safe operations, particularly during night flying or in low visibility conditions. These lights help other pilots and air traffic control determine the orientation, direction, and position of the aircraft. For example, the use of red and green lights on the wings helps to identify the aircraft's left and right sides, respectively, enabling pilots to gauge potential traffic conflicts or collisions.

Position lights do not primarily serve to improve visibility for pilots during the day, comply with flight plan requirements, or signal ground crew during takeoff. While pilots may benefit from the presence of position lights in terms of overall situational awareness, their main function relates to communicating the aircraft’s position to others, contributing to a collective understanding of air traffic.