Shortest flying route between JFK and Heathrow?

Question

Assuming a Trans Atlantic plane was allowed to fly straight across the Atlantic, I know about the engine thing and 500 miles from Iceland.
Anyway, would the curvature of the earth cause the plane flying straight between these two points to travel further out from the earth befroe turning back, thus travelling further than if it had travelled via the current route and thus travelling diagonally across the curvature of the earth.

I am curious because the Earth is fatter at the equator than at the poles. Therefore I am wondering if that comes into the equation to fly North from London before turning South over Iceland?

Answer 1

When an airliner flies from NYC (or any other eastern USA city) toward western Europe, it flies up along the eastern coast of north America all the way up until approx. over Newfoundland and begins to gently head in a more easterly direction. In most cases, the craft will fly over the southern tip of Greenland and Iceland before coming back down over the UK.
Lots of newer generation aircraft will have a GPS tracking satellite map to show you the exact route as well and you can see the land below and pick out landmarks and cities as you pass them from above. The curvature of the earth makes it look like you are traveling in a more dramatic arch northward than you actually are. You are traveling in more of a straight line than you think and only makes sense when you track this on a spherical map (globe) than a 2-d map.

TO ANSWER YOUR UPDATE: The Earth is not fatter at the equator, its a sphere and basially the same all over. If you flew in a perfect straight line on a flat map, you'd be flying further than whata typical airliner travels to Europe by flying what appears to be in an arc.

Answer 2

I'm not sure I completely follow your question, but the shortest distance between any two points on a sphere is a geodesic, which appears on a map as a curved line. To find it you'd draw a line around the world that divides it equally in two (assuming the world is a perfect sphere), and goes through your points (London and New York). The shortest distance you can take between them is the distance between your two points on this line.

So the shortest route to fly across the Atlantic would be along the geodesic between London and New York.

Answer 3

You are thinking of a curved surface, as a piece of paper. A globe acts differently. The farther north you go from the equator, the more you will need to travel north to keep the shortest route.

Answer 4

Your question is slightly off. Since planes fly at constant altitude, the planes never travel "further out from the Earth," on one route versus another. The shortest distance between any two points on Earth is on the circle that has those two points whose center is the center of the Earth:
http://en.wikipedia.org/wiki/Great_circle
http://en.wikipedia.org/wiki/Geodesic

Answer 5

Take a heading of 50 degrees and fly 4600 mi. the curve has no effect.

Answer 6

As the crow flies.