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Old 17th Jun 2012, 17:27
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FlightPathOBN
 
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Genghis,

I assume that you are asking about the A380 wake? I have not published anything about about this aircraft yet, as the data collection is still ongoing.

There are a few significant factors that influence the creation of the wake turbulence on final. Flaps are the most significant factor in vortex creation. (as noted with the 737-400 with outboard flaps vs 737-800 without, or flap setting 25 vs 30/40). Think about this, on final in a crosswind, the AC is crabbing, exposing one wing more than another, so you have a completely different vortex off of each wing...(in all the illustrations about crosswind blowing the vortex out of the way, they are incorrect, and actually, the vortex rollup can be increased on one side and decreased on another...I have even seen them rollup and bounce along the wind like a stone skipping on water)

The GPA is another, and a shallower GPA tends to reduce the strength and velocity of the vortices.

What I will also note on the A380, is a slow FAS, and that once the wheels are down, the airflow is so scrambled, that the turbulence doesnt rollup...
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