What color lights are used to identify the approach end of runways?

Green lights are used to identify the approach end of runways. This is a standard visual cue for pilots, as green lights signify that they are approaching the runway safely. The use of green lights helps pilots to clearly distinguish the runway's location, especially during landing approaches in various visibility conditions.

In addition to their color, green lights provide a contrast against the sky and the ground, enhancing their visibility during both day and night operations. This consistent use of green lights aligns with international aviation standards, ensuring that pilots worldwide can reliably interpret runway markings regardless of their location.

The other colors have specific meanings within aviation infrastructure but do not serve the purpose of indicating runway approach. Red lights are typically used on the ends of runways to indicate the runway's termination or on obstructions to warn pilots. Yellow lights may be used for taxiway indications, while blue lights are used on the edges of taxiways to delineate them. Thus, identifying the approach end of runways is specifically achieved through the use of green lights.