When air passengers brace themselves for a bumpy landing in bad weather, it's unlikely they give much thought to what is happening outside their windows.
But these pictures of a Swiss Air jet about to touch down at night on a fog-shrouded runway at Zurich Airport reveal what happens when a plane's wings cut through the air - to quite spectacular effect.
As the Airbus A340 glides towards the earth, floodlights over the runway illuminate the spirals of fog left in its wake.
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Spirals: The footage reveals what happens around the wings of a plane as it descends towards the earth to spectacular effect
The patterns created in the swathes of lit-up fog render the downwash, the ground effect and the wingtip vortices visible to the viewer, according to Jalopnik.com.
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Wingtip vortices are circular patterns of rotating air left behind by a plane's wing, while the downwash refers to the air forced down by the aerodynamic action of the wing in motion.
The phrase ground effect describes the increased lift and decreased drag a plane's wings generate when they are close to the earth.
Patterns: The wings of the plane create swirls in the fog over the runway at Zurich Airport
Stunning: The wings of the Swiss Air jet create spirals in the clouds of fog in the night sky
Touch down: The illuminated fog illustrates the downwash, the ground effect, and the wingtip vortices