# Why do planes generally curve north and not south? [duplicate]

I know that the shortest distance on a sphere is a curve and not a straight line, so that's why planes curve when they fly. But why is that planes curve north and not south? For example, when if I hop on a plane from New York City to London, it'll go northward and fly over Greenland. Could the plane have traveled in the same time but using a route that curves south?

• If you want the planes to "curve south" (at least how it appears on your map), try flying in the southern hemisphere. Commented Jun 10, 2020 at 4:05
• Why do I need to be in the southern hemisphere?
– Nate
Commented Jun 10, 2020 at 4:07
• The shortest distance between two points on a sphere is a straight line. At least, it is when you draw it on a globe. However, when you project that onto a flat map, the shortest path appears to be a curved path. It's not though, it's still straight. The map projection is just messing up your perception of what "straight" and "curved" are. Note that the map projection also distorts all other features, such as coastlines, in the same way. Commented Jun 10, 2020 at 4:13
• This does answer my question! Thank you
– Nate
Commented Jun 10, 2020 at 4:15
• @Nate, get a globe, a piece of string, and a flat map. Pick an origin/destination pair, and use the string to find the shortest “great circle” route between them on the globe. Note some geographic features that the route passes through, and plot them on the flat map. Now do it in the Southern Hemisphere... Commented Jun 10, 2020 at 4:48