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United States Department of TransportationUnited States Department of Transportation

Runway Status Lights

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Runway Status Lights is a fully automatic, advisory system designed to reduce the number and severity of runway incursions and prevent runway accidents while not interfering with airport operations. It is designed to be compatible with existing procedures and is comprised of Runway Entrance Lights (RELs) and Takeoff Hold Lights (THLs).

The FAA developed Runway Status Lights as part of an ongoing effort to explore new technologies. The system aims to improve air crew and vehicle operator situational awareness through accurate and timely indication of runway usage.

Runway Status Light systems are commissioned at twenty US airports as shown below:

Map of The United States showing airports that already have or are currently testing RWSL arrays SEA SFO LAX SAN LAS PHX IAH DFW MSP ORD DTW BOS JFK LGA EWR BWI IAD FLL MCO CLT


Runway Status Lights tell pilots and vehicle operators to stop when runways are not safe. Embedded in the pavement of runways and taxiways, the lights automatically turn red when other traffic makes it dangerous to enter, cross, or begin takeoff. The lights provide direct, immediate alerts and require no input from controllers. Runway Status Lights are operational at 20 airports across the US.

Pilot Reference Guide

Runway Status Lights is a fully automated system that provides runway status information to pilots and surface vehicle operators to indicate when it is unsafe to enter, cross, or takeoff from a runway. The Runway Status Lights system processes information from surveillance systems and activates Runway Entrance Lights and Takeoff Hold Lights in accordance with the motion and velocity of the detected traffic. Runway Entrance Lights and Takeoff Hold Lights are in-pavement light fixtures that are directly visible to pilots and surface vehicle operators. Runway Status Lights is an independent safety enhancement that does not substitute for an Air Traffic Control clearance. Clearance to enter, cross, or takeoff from a runway must still be issued by Air Traffic Control. Although Air Traffic Control has limited control over the system, personnel do not directly use, and may not be able to view, light fixture output in their operations.

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Vehicle Operators Training

Runway Entrance Lights

The Runway Entrance Lights system is composed of flush mounted, in-pavement, unidirectional fixtures that are parallel to and focused along the taxiway centerline and directed toward the pilot at the hold line. A specific array of Runway Entrance Lights include the first light at the hold line followed by a series of evenly spaced lights to the runway edge; and one additional light at the runway centerline in line with the last two lights before the runway edge (See FIG 2-1-9). When activated, these red lights indicate that there is high speed traffic on the runway or there is an aircraft on final approach within the activation area.

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Airport Diagrams

RWSL Videos

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