Why not a aircraft take the shortest route from US to australia ,why it rounds the earth to reach there?

Answer 1

By long route it depends on how you look at it. Because maps stretch out the spherical shape of the earth onto a 2D rectangle of paper there is quite a bit of distorsion.

You may also loose perspective on relative distances as well.
Many times it is shorter to fly northly towards the pole than head straight west following a lattitude. When taking this shorter route this is called a great circle route.

There are three types of maps which project the 3D spherical shape of the earth on a 2D flat map surface. The main one we are most familr with is called a mercator projection. The map was drawn by wrapping a cylinder of paper around a sphere (representing the earth) at its equator. The land masses are projected onto the paper as if a light were shining from the center of the sphere. The Shadows of the landmasses are projected on to the paper and traced out.

The only real points of the mercator map which are not distored are those where the paper is touching the equator. the further north you go on the map the more distorsion there is. You loose the sense of the spherical shape of the earth

Now if you were to plot a course from one point on the equator to another point on the equator. You would travel either straight east or west in a straight line . This would be the shortest course. To fly over either pole would be much longer.

how ever as you travel further north the curvature of the earth has more of a factor in the actual distance vs the apparent distance represented on a map.

So on a mercator projection map if you draw a straight line between two points you really have not connected the points by the shortest distance. (This is called a Rhumbline) To actually plot the shortest course between two points you have to draw a curved line (Compensates for curvature of the earth) This curved line is called a "Great Circle Route"


(There are other types of maps such as conical projection where a straight line is the shortest distance but I've already droned on long enough)

Answer 2

Actually, the curved path you see on a 2-dimensional map IS the shortest path.

"The great circle on the spherical surface is the path with the smallest curvature, and hence an arc (an orthodrome) is the shortest path between two points on the surface. The distance between any two points on a sphere is known as the great-circle distance. When intercontinental airline routes are drawn on a flat map (for instance, the Mercator projection), they often look curved. This is because they lie on great circles. A route that would look like a straight line on the map would actually be longer."

From Wikipedia, the free, online encyclopedia at:
http://en.wikipedia.org/wiki/Great_circle

Answer 3

The shortest route is to take a rounded path that matches the curvature of the Earth. This simplest way to see this effect is to get yourself a globe and a piece of string. Hold the string as tight as you can in a straight line between two points such as US and Australia. Then let the string curve around the Earth, you will see that the curved string is shorter than the taught, straight string.

Answer 4

Because a Great Circle route, which is what you're talking about, IS the shortest route. It is the analogue, on a spherical surface, of a straight line on a plane.

Answer 5

If I'm not mistaken, There are certain zones that are "no-fly" or unsafe or unfriendly for commercial planes as well as other craft. Although it would be more convnient to take the shortest route, planes are governed by such air traffic rules.

Answer 6

The "shortest route" from the US to Australia would go through quite a bit of magma. It's much safer to go around it. The fact is that our current technology won't allow travel through molten rock.

Answer 7

They've got special shoes. They're called Glue Shoes and have been all the rage since Australia was discovered! With Glue Shoes, Australians and their cute koalas and kangaroos and other animals (yes cuutie animals wear them too) don't fall off Earth.

Answer 8

Because it needs to stop to refuel and let off people who not going all the way to Australia, like Hawaii !