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
That’s easy, but doesn’t have anything to do with the op.
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