Why does flying east take longer flying west?

The planet is rotating "to the right" when viewed from outer space with the north pole at the top. It is rotating to the east.

To fly towards a destination in the east, your destination is always moving away from you.

To fly towards a destination in the west, your destination is always moving towards you.

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An even greater influence is the constant high-speed winds high in the atmosphere, known as the "jet stream". The prevailing direction of the jet stream is west-to-east. Commercial jet airliners flying east intentionally enter the jet stream whenever possible, and get a lot of help from it, decreasing the time required to cover an eastbound distance. When flying west, however, the jet stream can't help because it's flowing the wrong way; and if Air Traffic Control places your westbound flight at an altitude where you're in the jet stream, then you're flying against it, and it increases the time required for you to get anywhere.

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The first answer is simply wrong -- it looks sensible but so did the idea that heavier objects fall faster than light ones until Galileo did the experiment that disproved that. Here's one that would disprove the "direction of rotation" theory: Imagine a large north-polar projection map of the Earth on a flat plate resting on a turntable that turns slowly (say 1 rpm) in a counterclockwise direction (as the earth itself does from that angle), and give it a raised edge so that things moving around on top of the map won't fall off the edge. Place a small wind-up car alongside the turntable fence going in an eastward direction and measure how long it takes to go around the circle -- first clockwise (against the rotation) and then what the Brits call anticlockwise (with the rotation). Of course, those opposite-direction times will be the same, because there is no jet-stream effect.

Other evidence of the error is provided by the fact that differences in east-west and west-east travel times only appear for airplanes affected by the jet stream. They do not appear in automobile or railroad timetables, nor do they appear in flying times for low-flying planes. Artificial satellites would also be exempt, except that they always travel in an eastward direction, having taken advantage of the earth's speed of rotation in that direction (1000 mph at the equator) before they are launched.

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