Definition
A runway lighting system consisting of flush-mounted lights installed along the centerline of the runway at uniform intervals, providing visual guidance to pilots during takeoff, landing, and rollout in low-visibility conditions. The lights are white for most of the runway, transition to alternating red and white over the final 3,000 feet, and become solid red over the last 1,000 feet to indicate the approaching end of the runway.
Plain English
A line of lights set into the surface of the runway, right down the middle, to help pilots stay aligned with the runway when visibility is poor. The colors change near the end of the runway to warn pilots that they are running out of pavement.
Context Anchor
Seen in NOTAMs, runway lighting descriptions, and approach or landing planning, especially for night or low-visibility operations.
Why Pilots Care
These lights enable precise directional control on the runway when other visual references are limited or absent.
Grounding Statement
Picture a straight line of lights set into the runway pavement, marking the path your wheels should follow down the middle.
Intuition Check
Do not read RCLL as just any runway lights. It means the specific light system on the runway centerline, not the lights along the runway edges.
Example Sentence 1
The RCLL guided us straight down the runway during the low-visibility landing at night.
Example Sentence 2
Runway centerline lights allowed safe taxi and takeoff on the lighted runway.