No one in the history of man has been able to measure that curvature, even over calm or frozen water.
A math equation to show how much curvature the earth has, concluding about 8 inches a mile
Even ancient scientists calculated the earth's curvature: https://en.wikipedia.org/wiki/Eratosthenes#Measurement_of_the_Earth.27s_circumference
An article telling you how you can calculate the earth's size by the stars at different locations
A 2000 year history of how people have measured the earth's curvature
Now go ahead and say these all don't count because they're faked by nasa or are just optical illusions or something