Definition
A pair of light bars placed at each end of the runway that mark the boundary between the usable runway surface and the area beyond it. They show red to a pilot looking at the departure end of the runway (the end being left behind) and green to a pilot approaching the landing threshold.
Plain English
Lights at each end of the runway that tell you where the runway begins and where it ends. Green means the start of the runway as you arrive; red means the end of the runway as you depart.
Context Anchor
You see runway end lights during night operations or low-visibility operations when identifying how much runway remains ahead of you.
Why Pilots Care
They mark the absolute end of usable runway so pilots can judge remaining distance and avoid going off the pavement.
Intuition Check
Do not assume “runway end lights” means any lights near the end of the airport pavement. In this context, they are specifically the red lights that mark the end of the usable runway from your direction of travel.
Example Sentence 1
On final approach at night, the green runway end lights confirmed the threshold and helped the pilot judge the touchdown point.
Example Sentence 2
Before takeoff the crew checked the position of the runway end lights to confirm enough runway length remained.