What color is indicated by the left lights on an aircraft?

The left lights on an aircraft are red in color. This is a standard convention in aviation to aid in navigation and collision avoidance. Red lights on the left wing help pilots and other aircraft determine the orientation and heading of the aircraft.

This color code is part of the International Civil Aviation Organization (ICAO) rules, which specify that the left side of the aircraft should have a red light, while the right side has a green light. This differentiation allows for immediate recognition of an aircraft's position relative to another, which is crucial during nighttime flying or in low visibility conditions.