Ever wonder why your plane is flying in a curve when compared to flying straight on an inflight map of a long-haul flight?
This is especially noticeable when flying between Europe & the U.S., when aircraft fly over Greenland & Northern Canada instead of just flying from A to B like it would appear on a map.
This is due to simple math and physics. Because of its spherical shape, the Earth’s circumference is much larger around the Equator than at higher or lower latitudes towards poles.
The “Great Circle Route” is a flight that circles the Earth’s smaller circumference. It is also noticeable on flights from the U.S.A to Asia. These flights will fly much higher than the straight line and far more above Alaska and Siberia.
It is possible to draw a line around the globe from the middle, where it is the widest, instead of towards the North or South poles. This allows for the separation of distances and saves you a lot of time as well as fuel.
The Earth rotates around its axis so the equator has to “bulge out” in order to be larger. Contrary to popular belief, the Earth isn’t flat. This makes curvature an important aspect of the routes that aircraft follow. Aerial aircraft follow the Earth’s curves, and so they take flight routes that look like a curving line.
Before an aircraft takes off, flight paths are drawn. These routes will be determined based on the most efficient and shortest route. Flight paths can also change depending on weather conditions, wind, and jetstreams.
Jetstreams, in addition to the curvature and the Earth’s surface, are another reason why an aircraft might not follow a straight route. Sometimes, jetstreams can produce tailwinds of up to 200 miles per hour. This will allow an aircraft to travel faster and burn less fuel. Flight planning might consider alternative routes if the aircraft is flying into a wind speed of 200 miles per hour.