https://www.whiteeagleaerospace.com/first-flight-over-the-south-pole/
http://www.classichistory.net/archives/first-polar-flight
And somehow they accomplished this without compasses working. Which later proved problematic in 1979:
https://www.history.com/this-day-in-history/plane-crashes-over-antarctica
Yes, that is one belief. But you can't just type a reply assuming everyone reading it knows that's what you were thinking. Where as the flat earth model is a little more self explanatory. Your theory also flies in the face of reality were flights do travel over the north pole.
When I typed my first comment it was tongue in cheek imagining earth as a snowglobe shape flat on the bottom and bulbous on the north half.