Where airlines fly

Where does airlines fly?

To make the flight as fuel efficient and economical as possible, airlines want to fly the direct path between destinations. The shortest distance between two points on the surface of the earth is the so called Great Circle. A Great Circle is a circle passing through both points on the surface of the earth, and in the same time pass through the center of the earth.

By constantly calculating the change in the flight's heading (True Track) we can fly the shortest distance between two points. The Great Circle navigation becomes practical mostly over great distances.

This image from Wikipedia visualize the international flight routes.

www.flightradar.com

A rather quiet night in European airspace. You can see the aircraft cluster up around the airport hubs.

The aircraft fly along air corridors or are cleared directly to the destination.

Part of German Upper Airspace.

An example of a Rout Chart - Part of the Upper German Airspace.