Southern Hemisphere Flights

These flights exist:

  • Sydney-Santiago QF27/QF28
  • Sydney-Johannesburg QF63/QF64
  • Johannesburg-Sao Paulo SA222/SA223
  • Sao Paulo-Luanda DT747
  • Perth-Johannesburg SA281
  • Santiago-Melbourne LAN805

None of the work on flat earth. Flat earthers try to claim it does because of jet streams. Let’s look at the claims they make for Sydney-Santiago:

  • They claim the plane cruises at 650 mph
  • They claim the plane flies at 45,000-51,000 feet
  • They claim there are 350 mph tail winds

Here is the real information:

  • The plane is a Boeing 787-9
  • Cruises at Mach 0.85 which is 650 mph or 1050 kph airspeed.
  • The top speed is Mach 0.90 which is 690 mph or 1111 kph airspeed.
  • Cruising altitude 35,000-43,000 feet
  • Maximum Operating Altitude: 43,100 feet or 13,137 meters
  • Citation: Qantus profile for 787
  • Citation: EASA Data Sheet for 787

On the globe the distance is computed using the Haversine formula. I used the Haversine formula directly copied from David Weiss’s app that he ironically uses to determine distances within the app. 7,060 miles or 11,347 km.

This flight, taking the shortest route on the globe, without winds will take 10.9 hours. A headwind will slow it down and a tail wind will speed it up.

On flat earth you use the Polar distance formula which is a coordinate system transform of the pythagorean theorem. Walter Bislin has a web app to do this easily. 15,950 miles or 25,669 km.

This is the shortest line distance on flat earth crosses the North Pacific, enters the United Stated west coast, crosses Mexico and the north west coast of South America. In reality this flight heads south from Sydney, is south of New Zealand, skims the coast of Antarctica close enough to sometimes see icebergs in the ocean out the southern facing windows. Passengers never see the United States as the straight line flat earth flight requires. This greatly increases the flat earth distance.

In December a YouTuber, Critical Think, flew from Sydney to Santiago and back. The precise latitude and longitude points from the flight were tracked. This enables using the Polar Distance Formula to determine the flat earth distance of the entire flight.

The flat earth distance for flight QF27 on December 10, 2024 is 37,993 km or 23,608 miles. More than triple the globe distance.

We need to explore one more thing before pulling it all together: winds. Flat earthers use https://bobwinds.com/ to search for jetstreams. This shows winds at elevations based on pressure.

  • 250 hPa is typically found at an altitude of approximately 34,000 to 36,000 feet
  • 70 hPa is typically found at an altitude of approximately 59,000 to 61,000 feet
  • 10 hPa is typically found at an altitude of approximately 100,000 to 101,700 feet

Flat earthers claim 350 mph tail winds in both directions. Every day. But even their preferred source doesn’t support this. Look at Bobwinds and find a 35 mph wind at the elevations that planes fly. You won’t. The fastest jet stream ever recorded is less than 300 mph.

The fastest ground speed ever recorded by a passenger airplane is around 840 mph:

This means that earhters are claiming that southern hemisphere flights ALWAYS encounter jetstreams faster than ever documented. And that the jetstreams are always in the direction the plane is currently flying. How? Maybe claim the winds are in different directions at different elevations? But Bobwinds doesn’t support this.

Just to humor them, even though none of this is true, let’s imagine these jetstreams exist and always are a tailwind. This means the 787 is plying 650 mph airspeed plus a 350 mph tailwind. That’s 1000 mph. Does it work?

On the the flat earth distance for flight QF27 from December 10, 2024 is 23,608 miles. This means the flight would take 23.6 hours. How long did it actually take? Less than 12 hours. In order to make this flight the plane would need to fly 2,000 mph. As fast as the SR-71 Blackbird.

Even with the lies about aircraft and wind the flat earth distance is still ridiculously impossible.

There are many such flights, and they all have the same problem for flat earth: