Definition
A runway edge lighting system with the brightest available intensity setting, used to mark the edges of a runway and adjustable through several intensity steps to suit visibility conditions.
Plain English
The bright white lights running along both sides of the runway, with a high setting available for use in poor visibility or at night.
Context Anchor
Seen on airport sketches, airport diagrams, and instrument approach charts as a note about runway lighting.
Why Pilots Care
Enables safe night and low-visibility operations by providing clear visual reference for runway alignment and touchdown.
Example Sentence 1
The ATIS reported that Runway 27 was equipped with HIRL, which helped during the approach in light rain at dusk.
Example Sentence 2
With the HIRL intensity increased, the runway edges became visible through the haze during the approach.