Plain English Meaning

A pattern of bright lights laid out in a line leading up to the start of a runway. They help a pilot see the runway and line up with it when descending through low cloud or poor visibility.

Full Definition

Configurations of high-intensity lights arranged in a specific pattern extending outward from the approach end of an instrument runway, providing pilots with a visual transition from instrument flight to visual flight during the final stages of an approach. Approach light systems vary in length, configuration, and capability, ranging from simple to full precision systems with and identification.