What are wing bars in approach lighting?
Two short bars of green light that stretch the threshold line out past both runway edges — the lateral “wings” a pilot meets where the white approach lights end and the runway begins.
A wing bar is a short row of green lights that runs outward from the line of the runway edge lights at the threshold, at right angles to it. There are two, one on each side of the runway, placed symmetrically about the extended centreline. On final approach the white centreline and crossbar lead the eye in, and the wing bars carry the green threshold line beyond both runway edges.
ICAO files wing bars under the runway lights, but they are read together with the approach lighting: they are the first green lights the pilot sees where the white pattern ends, and their extra width makes the threshold stand out. They are fixed, unidirectional lights showing green toward the approach, and their intensity and beam spread must suit the visibility and ambient-light conditions the runway is used in.
Frequently Asked Questions
Q1What are wing bars in approach lighting?
Wing bars are two groups of green lights at the runway threshold, one on each side of the runway, each running outward from the line of the runway edge lights. ICAO lists them with the runway lights, but a pilot reads them together with the approach lighting: the white approach pattern leads in, and the green wing bars mark the lateral limits of the threshold.
Q2How many lights make up a wing bar, and how far does it extend?
Each wing bar has at least five lights and extends at least 10 m outward from, and at right angles to, the line of the runway edge lights. The innermost light of each wing bar sits in line with the runway edge lights.
Q3What colour are wing bars, and who can see them?
They are fixed, unidirectional lights showing green in the direction of approach to the runway. They are not shown to aircraft approaching from the opposite direction.
Q4When are wing bars provided?
On a precision approach runway they are recommended where additional conspicuity is considered desirable. On a non-instrument or non-precision approach runway with a displaced threshold, they must be provided where threshold lights are required but are not provided.
Q5How are wing bars different from a crossbar?
A crossbar is white, forms part of the approach lighting system, and is laid across the extended centreline, 300 m from the threshold (and also at 150 m in CAT II/III). Wing bars are green, sit at the threshold, and extend sideways from the runway edge-light line rather than across the centreline.
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