What are wing bars?
Two groups of green lights that extend the threshold line outward beyond the runway edges, making the threshold stand out.
Wing bars are provided at the threshold in two situations: on a precision approach runway when additional conspicuity is desirable, and on a non-instrument or non-precision runway with a displaced threshold where threshold lights are required but not provided. They form two symmetrical groups about the runway centreline, each running outward from the line of the runway edge lights at right angles to it.
Each wing bar is green and unidirectional: it shows toward the approach and is not visible from the opposite direction. The innermost light of each bar sits in line with the runway edge lights, so the bar reads as the threshold row continued sideways.
Frequently Asked Questions
Q1What are wing bars?
Wing bars are two symmetrical groups of green lights placed at the runway threshold, each extending outward from the line of the runway edge lights to make the threshold more conspicuous.
Q2How many lights make up a wing bar?
Each wing bar has at least five lights, extending at least 10 m outward from, and at right angles to, the line of the runway edge lights. The innermost light sits in line with the runway edge lights.
Q3What colour are wing bars and which pilots can see them?
Green, and unidirectional: they are visible to pilots on approach and are not shown in the opposite direction.
Q4Are wing bars the same as threshold lights?
No. The threshold row spans the runway width between the edges. Wing bars continue that same line outward on both sides, outside the runway surface, to add conspicuity. On a non-instrument or non-precision runway with a displaced threshold, wing bars may be provided where threshold lights are required but not provided.
Q5When are wing bars provided?
On a precision approach runway when additional threshold conspicuity is desirable, and on a non-instrument or non-precision approach runway where the threshold is displaced and threshold lights are required but not provided.
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