Runway Status Lights
From Wikipedia, the free encyclopedia
Runway Status Lights are a new type of lighting system designed by the Federal Aviation Administration as part of its Runway Incursion Reduction Program. The lights, which turn red on the centerline of a taxiway or runway, advise pilots on their movement status. Runway Entrance Lights (RELs) illuminate when it is unsafe to enter the runway. Takeoff Hold Lights (THLs) illuminate when an aircraft is on the runway but it is unsafe to takeoff, due to other traffic movements on the runway. Although the lights will turn off once an aircraft has cleared the obstructing position, THLs turning off does not constitute a clearance to takeoff from a runway.
The system is currently being tested in the United States at Dallas-Fort Worth International Airport.
In the August 3, 2006 Notice to Airmen (NOTAM) [1], the FAA describes the system:
- RWSL is an advisory system for use by pilots and vehicle operators and helps maintain situational awareness. It operates independently of Air Traffic Control. Status lights have two states: ON (lights are illuminated red) and OFF (lights are off) and are switched automatically based on information from the airport surface surveillance systems. These surveillance systems include airport surveillance radars (ASRs), surface detection radars (ASDE-3 or ASDE-X) and multilateration information from the ASDE-X surveillance system.
