Wind Direction
Pilots prefer to take off and land facing into the wind. This has the effect of reducing the aircraft's speed over the ground (for the same given airspeed) and hence reducing the distance required to perform either maneuver.
The exception to this rule is at alpine airports (altiports) where the runway is on a severe slope. In these instances, takeoffs are usually made downhill and landings uphill, with the slope aiding in acceleration and deceleration.
Many airfields have runways facing a variety of directions. The purpose of this is to provide arriving aircraft with the best runway to land on, according to the wind direction. Runway orientation is determined from historical data of the prevailing winds in the area. This is especially important for single-runway airports that do not have the option of a second runway pointed in an alternative direction. A common scenario is to have two runways arranged at or close to 90 degrees to one another, so that aircraft can always find a suitable runway. Almost all runways are reversible, and aircraft use whichever runway in whichever direction is best suited to the wind. In light and variable wind conditions, the direction of the runway in use might change several times during the day.
Read more about this topic: Airfield Traffic Pattern
Famous quotes containing the words wind and/or direction:
“The wind and the rain, gives this place a gleam that just isn’t natural. And the ground, alive with crawling things, crawling death.”
—Edward D. Wood, Jr. (1922–1978)
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—Marshall McLuhan (1911–1980)