Traveling between Europe and North America? Why your plane doesn't fly "straight" (geometry has something to do with it)

If you take a look on Flightradar at the routes that planes take to fly from Europe to North America (and vice versa), you will easily discover that all or most 'climb' to Britain and Ireland and some even as far as Iceland before starting the actual Atlantic crossing.

The more to northern latitudes the planes head (again taking the case of flights from Europe to North America), the more their destination will be shifted westward.

Thus, for example, the Rome-Los Angeles will transit further north than the Rome-New York, even going so far as to fly over Greenland, before 'descending' to the western part of the North American continent. So do all the other carriers between Europe and the West Coast, as can be seen in the vintage photo taken aboard a British Airways Boeing 747 flying between London Heathrow and Las Vegas.

Yes, one may ask: but Why don't planes fly straight trajectories between two cities? They would if terraplattist friends were right and our planet was a disc. Since instead is a sphere, airplanes follow orthodromic trajectories, that is, those that allow two points on a sphere to be joined using the shortest line.

In the image taken from the Passion Astronomy website, you can see how orthodromic route connecting Moscow to New York is over a thousand kilometers shorter than the straight route. To date, due to war between Russia and Ukraine and sanctions imposed on the aggressor country, the route no longer exists. But when hostilities cease, by flying the Orthodromic route instead of the straight route, planes will once again take a good hour less to fly.

Just A ban on the use of Russian airspace. from February 2022 is causing no small consequences for European carriers flying to the Far East and some of those in the Far East flying to Europe.

All of them, before the Russian-Ukrainian war, traveled Orthodromic routes that passed over Siberia, precisely because they were the shortest in flight time and consequently the most economical in terms of fuel consumption. Now, these routes can no longer be flown, with the resulting in increased flight times of up to two hours and, consequently, substantial extra fuel expenses that were obviously reflected in ticket prices.

Then there are routes that, because of the geographical location of the connecting cities, cannot take much more advantage of the curvature of the earth: such is the case with those connecting Europe and South America, or Europe and Central America. There it is game to transit across the equator and thus fly over the 'widest' part of the planet. In this case (go look to believe) the routes taken by the planes are almost straight.

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