Building a tower to the heavens.
Sounds pretty high.
Nobody knows how high planes really fly.
Sure they do, it's called an altimeter. It measures the distance to the ground below.
And if a plane flies level at a set altitude, that proves a flat earth. If a plane flew level over a so called globe earth, the plane would continue to climb as the ball gets farther away.
You should go back and review middle school science class where they teach about gravity. By using your altimeter when you fly, you can maintain whatever altitude you choose.
From space.com
"But as you travel south, approaching the equator, Polaris sinks lower and lower toward the horizon. Once you’ve crossed that boundary, you can't see it at all — it's blocked by the curve of Earth in that direction.
Similarly, as you travel south, new constellations await your delighted gaze — ones that would be completely obscured by Earth's curve if you stayed up north.
There's another trick you can play, too. If you live in an especially flat area, you'll be able to see stars down to the horizon but no farther (because Earth is in your way). But if you travel up — say, to the top of a mountain — you get a better vantage point and can see stars farther down than you could before.
In fact, the ninth century Abbasid Caliph al-Ma-mun sent an expedition to do exactly that and used those observations to measure
Earth's circumference"
They have known about the curvature of the Earth for over a thousand years.
In fact, the ninth century Abbasid Caliph al-Ma-mun sent an expedition to do exactly that and used those observations to measure
Earth's circumference.