Why Planes Never Fly in a Straight Line

By Magari Poa on 25/08/2025

Have you ever looked at a flight tracker and thought: "Wait… why is my flight from New York to Tokyo curving over Alaska instead of just going straight across the Pacific?" At first glance, it seems like the pilots are taking the scenic route. But in reality, those curves in the sky are the shortest, safest, and often fastest ways to fly. Let's unpack why.

? The Science of the "Great Circle"

The Earth isn't flat (sorry, conspiracy theorists) — it's a sphere. On a globe, the shortest distance between two points is along something called a great circle route. If you stretch a string between two cities on a globe, that's the path planes aim to follow.

But here's the catch: when you flatten the Earth onto a 2D map, those great circles show up as curves. That's why flights from North America to Asia often look like they're "detouring" over the Arctic — when in fact, they're taking the quickest possible path.

A classic example: the flight from Los Angeles to London. On a map, you'd think the plane would zip straight east. But in reality, the fastest route nudges northward toward Canada, skimming near Greenland before dropping into the UK. That curved path cuts hundreds of kilometers off the journey compared to a "straight line" on a flat map.

?? Riding the Jet Streams

It's not just geometry at play. Winds in the upper atmosphere — especially the jet streams — massively influence routes. These are powerful rivers of air that flow west to east at around 160–320 km/h (100–200 mph).

Eastbound flights (like New York to London) often hitch a ride on these jet streams, cutting flight times by an hour or more.
Westbound flights (London to New York) have to battle against them, which is why return trips can feel longer.

In February 2020, a British Airways flight from New York to London broke records, crossing the Atlantic in just 4 hours and 56 minutes thanks to unusually strong jet streams — faster than many private jets.

?? Geography, Safety, and Politics

Routes aren't chosen just for speed. Airlines also have to factor in:

Airspace restrictions: Flights between Europe and Asia used to regularly cross Russian airspace, but after the 2022 invasion of Ukraine, many airlines were forced to reroute — adding hours to trips like London–Tokyo.
Emergency landing sites: Long-haul flights must stay within range of airports suitable for diversions. This is why transpolar routes are carefully regulated — pilots need safe "escape points" in case of emergencies.
Weather and storms: Pilots often curve around hurricanes, typhoons, or volcanic ash clouds (remember the 2010 Eyjafjallajökull eruption in Iceland that shut down European skies for weeks?).

?? Real-Life "Why Are We Going This Way?" Moments

San Francisco to Hong Kong flights arc north over Alaska and Siberia instead of crossing the Pacific head-on.
Doha to Los Angeles often swings up over the Arctic, tracing a near-polar path.
During the COVID-19 pandemic, when fewer planes were in the air, passengers noticed more obvious detours because airlines optimized flights for fuel savings rather than crowded routes.

? Beyond the Myths

Flat Earth communities love to use curved flight paths as "proof" of their theory. Ironically, the opposite is true: the way planes actually fly is one of the clearest demonstrations that Earth is round.

And from a business perspective? Every saved minute counts. Fuel makes up around 20–30% of an airline's operating costs, so shaving even a few hundred kilometers off a flight can mean millions saved annually. That's why airlines invest heavily in route planning software that balances great circles, winds, politics, and safety all in one.

? The Bottom Line

Planes don't fly in straight lines because the world isn't flat — and because nature, politics, and physics all have a say in how we move through the skies. What looks like a detour on your seat-back map is usually the smartest, fastest, and safest way to get you where you're going.

So next time you look out the window and wonder why your flight is hugging the Arctic or curving over oceans, remember: the pilot isn't lost. They're just following the invisible highways of the planet.

? Perfect for aviation nerds, curious minds, and anyone who's asked mid-flight: "Where the heck are we going?"