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Comment by k-mcgrady | Hacker News Reader

The article mentions weather but can anyone explain in more detail why flights don't always take this (bypassing USA) route? It seems much more direct. My only guess is safety (nowhere to make an emergency landing for most of this shorter route).

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The world is a sphere, the projections shown in the article don't reflect that. Russia is near the "top" of the world, so flying north is the quickest way to go south, on the opposite "side" of the planet.

Good point, I never thought about that.

Flat maps distort global distances. If you draw a direct line on a globe or Google Earth, you'll see why they take this path.

Google Earth screenshot: http://i.imgur.com/WyIxmC5.png

Regarding great circles and flight routes, a nice feature of Wolfram Alpha is that it will actually display the great-circle route as a straight line, so you can see where it goes:

http://www.wolframalpha.com/input/?i=moscow+to+havana

The projection is a polar projection about the origin, so great circles through Moscow are straight lines.

The route usually taken is closer to:

Great Circle Distance http://en.wikipedia.org/wiki/Great-circle_distance

Imagine that map on a sphere. The higher you go, the shorter the distance. If you flew directly over the North Pole you'd jump from one half of the map directly to the other.

The path over the US is the shortest path. http://en.wikipedia.org/wiki/Great-circle_navigation

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