The FAA’s newest runway safety enhancement tool, runway status lights (RWSLs), became operational on July 25 at Washington Dulles International Airport (KIAD). The new system uses a series of colored lights embedded in the runway and taxiway pavement to help prevent runway incursions by offering pilots and vehicle operators a simple visual system to determine whether it is safe to cross or enter a runway.

RWSLs serve as a backup to an ATC tower clearance, not a substitute. They automatically turn red when other traffic makes it dangerous to enter, cross or begin takeoff after gathering data from airport runway surveillance systems. Activation of runway entrance and takeoff hold lights requires no input from air traffic controllers and is synchronized with the motion and speed of air and ground traffic detected.

The FAA plans to install the new lights at 23 U.S. airports by year-end.