I have a math example you can try. Calculate the curvature of the earth. At the equator the earth is said to be ~24,000 miles long. From cruising altitude of a commercial airliner at 36,000 feet, you can see roughly 211 miles away. So you're in a plane at 36k feet, you see a mountain range that on google maps is 200 miles away. You can see the foot of that mountain. But here's the problem. With a circumference of ~24,000 miltes, something that is 200 miles away would be several miles DOWN the curve. Meaning, there is no way you could be seeing the mountain at all, let alone the foot of that mountain. You can run this experiment with pretty much anything if you're at some elevation like on a mountain or large hill. Find a structure like a windmill or building that you can see. Get the distance between you and that structure using gps or whatever, and you can calculate how far down the curve it would be. Also, snipers don't have to compensate for the coriolis effect. Befriend a professional sniper and get him drunk and he'l tell you they don't calculate for the curve of the earth.