What alert does a runway edge light system change from white to yellow indicate?

The alert indicating a change from white to yellow in a runway edge light system serves as a vital warning to pilots. This transition in color signifies that the aircraft is nearing a caution zone, typically the area close to the runway where specific attentiveness is required. This caution zone may involve transitions to taxiways or other areas that could pose safety considerations during landing or takeoff.

Understanding this signaling system is critical for ensuring the safety of flight operations, as it enables pilots to adjust their approach and maintain situational awareness during critical phases of flight where navigational and operational precision is paramount. The coloration helps differentiate between safe landing zones and areas that require increased vigilance, thus decreasing the likelihood of accidents or miscommunications on the airfield.