Flight route test

Southern Hemisphere flights

Direct flights linking Australia, Africa, and South America are the simplest test of the planet's shape. Compare the real flight time with the distance on a globe and on the “flat Earth map”.

Flat-earth claim

Direct southern flights do not exist or are hidden, because on a flat map those routes make no sense.

What the measurement shows

These flights exist and have timetables. Their duration matches the globe distance at a normal cruising speed. On the disc map the same route is 2–3 times longer, so the aircraft would have to fly at an impossible speed.

The popular “flat Earth map” is a north-pole-centred azimuthal equidistant projection. It stretches the south more and more toward the edge, so distances between Southern Hemisphere cities are hugely overstated on it.

Pick a route and compare three numbers: the real flight time, the speed implied by the globe distance, and the speed the disc-map distance would demand. Only the globe gives a speed consistent with real aircraft.

Choose a city pair. The calculator shows the globe distance and the disc-map distance, plus the speed each model would require given the real flight time.

Route test

Pick a non-stop flight

Airline
LATAM / Qantas
Scheduled flight time
12.5 h
Two maps, two answers
Distance on a globe
11,347 km
Distance on the disc map
25,684 km
Disc longer by
2.3×
Required speed — globe
908 km/h
Required speed — disc
2,055 km/h
The globe speed sits within the range of an ordinary passenger flight.
On the disc map this flight would need roughly 1.7× the speed of sound — passenger jets do not reach that. The route only works on a sphere.

Flight times are approximate (scheduled airborne time). The disc distance is measured on the north-pole-centred azimuthal equidistant projection — the popular “flat Earth map”.

What this shows
  • On a globe the required speed sits in the normal airliner range (~800–950 km/h).
  • On the disc map the same route demands supersonic speed, which passenger jets do not reach.
  • The farther south the route, the more the disc map inflates it — so it cannot be a map of the real planet.

Flights and flat Earth — questions

Yes. Sydney–Santiago, Johannesburg–Perth, and Santiago–Auckland, among others, run regularly. They have public timetables, and the flight time matches the distance measured on a globe.

Because the disc map (north-pole-centred azimuthal) stretches the Southern Hemisphere. Cities that are close on a globe are separated by an enormous gap on the disc — the aircraft would have to cover it in the same time, which is physically impossible.

Direct routes between southern continents cross the southern oceans, not the pole. Their length and duration fit a globe; the absence of flights directly over Antarctica is down to weather, regulations, and diversion airports, not a “barrier”.

Wind changes the time by a few percent each way, which is why an average of both directions is used. Even with that correction the disc-map distances stay overstated by hundreds of percent — wind cannot make that up.

See also

Continue exploring

Measure yourselfEratosthenes' experimentFind Earth's circumference with a shadow, as done 2,200 years ago.RoutesGreat circle vs rhumb lineDraw the shortest path on a sphere and a constant-bearing route.ArticleGreat circle vs rhumb lineWhy the shortest route looks like an arc on a map.MapDisc map (azimuthal)See how a north-pole centre stretches the south.Flat EarthFlat Earth — model vs measurementInteractive tools and six independent lines of evidence for Earth's shape.