Definition
A configuration of approach lights installed on the ground leading up to a runway threshold, designed to help pilots transition from instrument flight to a visual landing. MALS uses medium-brightness lights and is one of several standardized approach lighting systems specified by the FAA, providing visual guidance during the final portion of an instrument approach.
Plain English
A line of medium-brightness lights on the ground that lead a pilot toward the runway, helping them line up and see the airport when breaking out of cloud or low visibility on an approach.
Context Anchor
Seen on approach charts, airport lighting information, and airport notices about runway light outages.
Why Pilots Care
Provides critical visual cues that allow safe continuation of an approach when the runway environment is not yet in sight.
Intuition Check
“Medium intensity” describes the brightness level of the lights, not the importance or quality of the system. MALS is an approach light system; it is not the same as a version that adds flashing runway-alignment lights.
Example Sentence 1
The chart showed that Runway 27 was equipped with MALS, so the pilot knew to look for the medium intensity approach lights when nearing minimums.
Example Sentence 2
Runway 27 is served by a MALS, so the approach remains usable in visibility down to one mile.