Since this is all "known" and "proven" (your words), please provide this proof. Provide evidence that:
- GPS predicted distances are accurate
- Round Earth Latitude and Longitude are accurate
- Aircraft cruise speeds are measured in a way that does not use a Round Earth coordinate system
If you are making any of these claims, it is your burden to back up your argument and demonstrate it.
And herein lies the problem. Tom won't accept any evidence as valid. Period. We use GPS all day every day to get where we are going be it aircraft, shipping, or cars, but that isn't good enough. He wants things measured in a way that does not rely on RE coordinates. He knows that that is highly unlikely since the Earth is round and all coordinate systems reflect that. FE doesn't even have a workable map and yet the RE crowd is supposed to screw with their measurement systems? He even acknowledges the existence of GPS which is satellite based, but still clings to a dead theory.
Tom, if you are claiming the Earth is flat, the burden is on YOU. Prove that it is flat. I would love to see that.