If you have ever had a trans-continental flight (even a long distance flight in your country) you may have noticed that planes do not follow the shortest line between two destinations, on the contrary to this, they follow a quite curved route. Well, there are lots of reasons for this situation but the main reason is the shape of the world. The planet surface is not a straight serving dish as we all know, it is a global curve so that the shortest way between two destinations is not a straight line but a curved line.
In this case, when you try to measure the distance between two distant points such as Los Angeles and Ankara (Turkey), a complex line appears magnificently. Linear distance (also known as Rhumb Line, an arc crossing all meridians of longitude at the same angle) between Los Angeles and Ankara is 13.423 kilometers. On the other hand, if you want to find the ‘‘real’’ shortest distance, you need to use ‘‘Great Circle Method’’ by considering slant surface. After using this method you will find the distance 11.269 kilometers which is shorter than any other! Actually trans-continental flights are not curved but appears to be so, because all the maps you see are not a real representation of the Globe. If we put these lines on a two dimensional platform, the amazing nature reveals itself obviously. The real shortest distance on visual seems to be further than linear distance, but on Earth actually it is shorter.
A complicated and significant work!
Setting the course is also a complex business. The pilot flies the plane but the course is set by somebody on the ground. Those people are Air Traffic Controllers. This complicated system includes which plane will take off or land, which route is going to be use etc… When thinking thousands of planes take off and land in a day, it must be really hard job to organize all of them.
One more fact; all transoceanic flights must be near an airport at all times. For example, if you fly from New York to Berlin, you will notice that the plane curves towards Canada, then Iceland etc. There are airports for planes to land if any emergency cases occur like motor breakdown when they are above the ocean.