Do you know how reasoning works?
Specifically a proof by contradiction and circular reasoning?
What you are doing is circular reasoning, which is invalid. You assume a premise to try to prove (or at least avoid a disproof) of that premise.
That is not how reasoning works at all.
With a proof by contradiction, you start with a premise, argue through without making more assumptions, until you reach a contradiction which you then use to conclude the assumption was false.
You start with the assumption that the Earth is flat. These flights clearly are NOT impossible. Thus, these flights are possible on a flat Earth.
No.
To do it properly (i.e. using reasoning and logic), but I'll even be nice and start with your BS assumption:
Assume Earth is flat.
These flights are impossible on a flat Earth.
Thus these flights are impossible.
But these flights happen, and thus are possible.
Thus we have reached a contradiction and thus the assumption (that Earth is flat) is FALSE!!!
You cannot just start with the assumption that Earth is flat to try and prove these flights are possible on a flat Earth.
You need to deal with why they are impossible.
This is more of another map problem if anything.
Yes, as the distances make these flights impossible on a flat Earth.
You have the general connectivity of places on the globe, based upon flights, including their directions and times.
This requires both the north pole and south pole to be small regions (or points). It also requires the equator to be much larger.
With these connections going all around the world, there is no way to fit this on a flat Earth.
You could use the standard NP centered AEP, but that fails with flights near the south pole.
You can use the SP centered AEP, but that fails with flights near the north pole.
You can use the bipolar map, but that fails with flights which go from one side to the other.
There is no way you can fit these flights onto a flat Earth while keeping them possible.
So it doesn't matter if you assume Earth is flat or not. These flights are impossible on a flat Earth.
Thus these flights being possible show Earth cannot be flat.