34) Ship captains in navigating great distances at sea never need to factor the supposed curvature of the Earth into their calculations. Both Plane Sailing and Great Circle Sailing, the most popular navigation methods, use plane, not spherical trigonometry, making all mathematical calculations on the assumption that the Earth is perfectly flat. If the Earth were in fact a sphere, such an errant assumption would lead to constant glaring inaccuracies. Plane Sailing has worked perfectly fine in both theory and practice for thousands of years, however, and plane trigonometry has time and again proven more accurate than spherical trigonometry in determining distances across the oceans.

People have believed that the Earth is flat since the beginning of humanity, but the modern Flat Earth hypothesis stemmed from an experiment called the Bedford Level Experiment, conducted in the mid-1800s by a man named Samuel Rowbotham.[1] Rowbowtham, who wrote a book named Earth Not a Globe, started the modern movement by debating scientists publicly and accumulating followers. In the experiment, Rowbowtham attempted to measure the curvature of the earth by observing the curvatures at a local river. He took his results as disproving the theory of a round earth, but future scientists have said that the results he obtained could be accounted for by the parallax effect.[2]
103) There are several constellations which can be seen from far greater distances over the face of the Earth than should be possible if the world were a rotating, revolving, wobbling ball. For instance, Ursa Major, very close to Polaris, can be seen from 90 degrees North latitude (the North Pole) all the way down to 30 degrees South latitude. For this to be possible on a ball-Earth the Southern observers would have to be seeing through hundreds or thousands of miles of bulging Earth to the Northern sky.

158) If “gravity” magically dragged the atmosphere along with the spinning ball Earth, that would mean the higher the altitude, the faster the spinning atmosphere would have to be turning around the center of rotation. In reality, however, if this were happening then rain and fireworks would behave entirely differently as they fell down through progressively slower and slower spinning atmosphere. Hot-air balloons would also be forced steadily faster Eastwards as they ascended through the ever increasing atmospheric speeds.
Can someone make me understand of Curvature feet calculation which is mentioned in several proofs. As in 71 number proof ( or several other distanced based proofs ) That the Observer distance is 60 miles sea-level from Chicago buildings which should be 2,400 feet below the horizon. As per Nasa earth curvature goes down 8 inches per mile. 72 inches(6 feet) and 60 miles contain 60 x 8 = (480 inches) that is equal to (480/12) = 40 feet. How does it count to 2,400 feet?
45) On a ball-Earth, Johannesburg, South Africa to Perth, Australia should be a straight shot over the Indian Ocean with convenient re-fueling possibilities on Mauritus or Madagascar. In actual practice, however, most Johannesburg to Perth flights curiously stop over either in Dubai, Hong Kong or Malaysia all of which make no sense on the ball, but are completely understandable when mapped on a flat Earth.
24) If Earth and its atmosphere were constantly spinning eastwards over 1000mph then North/South facing cannons should establish a control while East-firing cannonballs should fall significantly farther than all others while West-firing cannonballs should fall significantly closer. In actual fact, however, regardless of which direction cannons are fired, the distance covered is always the same.
15. The idea that, instead of sailing horizontally round the Earth, ships are taken down one side of a globe, then underneath, and are brought up on the other side to get home again, is, except as a mere dream, impossible and absurd! And, since there are neither impossibilities nor absurdities in the simple matter of circumnavigation, it stands without argument, a proof that the Earth is not a globe.
119) It is claimed that the other planets are spheres and so therefore Earth must also be a sphere. Firstly, Earth is a “plane” not a “planet,” so the shape of these “planets” in the sky have no bearing on the shape of the Earth beneath our feet. Secondly, these “planets” have been known for thousands of years around the world as the “wandering stars” since they differ from the other fixed stars in their relative motions only. When looked at with an unprejudiced naked-eye or through a telescope, the fixed and wandering stars appear as luminous discs of light, NOT spherical terra firma. The pictures and videos shown by NASA of spherical terra firma planets are all clearly fake computer-generated images, and NOT photographs.
195) Astronomers say the magical magnetism of gravity is what keeps all the oceans of the world stuck to the ball-Earth. They claim that because the Earth is so massive, by virtue of this mass it creates a magic force able to hold people, oceans and atmosphere tightly clung to the underside of the spinning ball. Unfortunately, however, they cannot provide any practical example of this on a scale smaller than the planetary. A spinning wet tennis ball, for instance, has the exact opposite effect of the supposed ball-Earth! Any water poured over it simply falls off the sides, and giving it a spin results in water flying off 360 degrees like a dog shaking after a bath. Astronomers concede the wet tennis ball example displays the opposite effect of their supposed ball-Earth, but claim that at some unknown mass, the magic adhesive properties of gravity suddenly kick in allowing the spinning wet tennis ball-Earth to keep every drop of “gravitized” water stuck to the surface. When such an unproven theory goes against all experiments, experience and common sense, it is high time to drop the theory.
3) The natural physics of water is to find and maintain its level. If Earth were a giant spinning sphere tilting and hurling through space then truly flat, consistently level surfaces would not exist here. There would be a massive bulge of water in the oceans because of the curvature of the earth. If earth was curved and spinning the oceans of water would be flowing down to level and covering land. Some rivers would be impossibly flowing uphill. There would massive water chaos and flooding! What we would see and experience would be vastly different! But since Earth is in fact an extended flat plane, this fundamental physical property of fluids finding and remaining level is consistent with experience and common sense. The water remains flat because the earth is flat!