This SAFO serves to ensure that aircraft operators, pilots and airport personnel are aware of the installation, meaning, and use of RWSLs.
There have been several instances at RWSL airports where flightcrews have ignored the illuminated red in-pavement RWSL lights when issued a clearance by Air Traffic Control (ATC). Illuminated RWSLs mean aircraft/vehicles stop or remain stopped and contact ATC for further direction, relaying to ATC that the RWSLs are illuminated. The RWSL system operates independently from ATC and controllers do not have any indication of when the RWSL lights are illuminated. Failure to comply with illuminated red in-pavement RWSL lights may result in a high risk collision Runway Incursion event.