PPRuNe Forums - View Single Post - Fleet grounded at 7kts??
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Old 27th Jan 2015, 16:29
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9 lives
 
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Think in terms of "boundary layer". There is the wind speed, and closer to the ground, the earth's boundary layer will begin to have an effect, which will be to slow the wind. Of course, many factors will affect this, so you can't usually quantify these effects. However, they will result in some wind speed reduction very close to the surface. Beware that any topographic "funneling" could cause an opposite effect, but generally, airports are not found where a crosswind funneling effect is fa big problem.

Also, as the aircraft comes into ground effect, the flight controls will be just a bit more effective. Thus, if you can maintain the runway heading with precision down final approach, chances are good that it'll become more easy close to the surface.
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