What color are runway threshold lights?

Runway threshold lights are green to indicate the beginning of the usable portion of the runway for landing aircraft. These lights help pilots identify the threshold, particularly at night or in low-visibility conditions. The green lighting provides a clear visual cue that enhances situational awareness during the approach and landing phases of flight. Understanding their color and function is essential for ensuring safe operations at airports.

The other colors listed are associated with different aviation lighting systems: red lights typically indicate the runway's end or provide warnings for various hazards, orange lights are often used for caution and warning signals, while blue lights denote taxiway edges. Each color serves a specific purpose in aviation navigation and communication, but for runway thresholds, green is the defining color.