The only Flat Earther I am aware of who has proposed a mostly working model is Mark Sargent.
Mark Sargent says we are living on a flat Earth, and all of the things we see in the sky are “projections” on a solid dome. Beyond this dome is undefined – the sum total of our reality exists under the dome. If we look through a telescope at the planets in the sky, we will see more detail than we do with the naked eye because the technology responsible for displaying the projections is advanced, and the projections themselves are very detailed.
This is a model that can be used to explain almost everything we observe, since it can just claim all astronomical phenomena are this projection deception.
Unfortunately for his Mark, there are some serious issues with his explanation.
Southerly Navigation
If Mark’s model is correct, the distance between longitudinal lines must increase as we go south, because they radiate out from the North Pole. A map of his model can be made to match our observations from the North Pole to the Equator, but it will fail to match observation as we move south of the Equator. And, the further south we go, the more his model falls apart. Mark’s flat Earth map relies on expanding the oceans between the continents South of the Equator, in order to still get the land masses to look almost right. But, if the Earth is flat, then all of the distances between two points south of the Equator on every map we use must be wrong. Let’s explain.
Pick any four points on any map of the Earth using these rules:
1) A and B must be on the same lattitude.
2) C and D must be on the same lattitude.
3) A and C must be on the same longitude.
4) B and D must be on the same longitude.
5) A and B must be on different longitudes.
6) A and C must be equidistant from the equator.
If Mark is correct, the distance between A and B (call it A_B) must be shorter than C_D. If the Earth is spherical, A_B must be identical to C_D. Let’s check it out, I’ll use Google Maps.
A. 30N, 20E
B. 30N, 115E
C. 30S, 20E
D. 30S, 115E
According to Google Maps, A_B and C_D both equal 5,483 miles.
If the Flat Earth model is accurate, A_B should be significantly smaller than C_D.
This proves one of two things: either Mark’s model is wrong, or Google Maps is wrong. If Google Maps is wrong, then no one South of the Equator uses Google Maps, or they don’t care or realize that it’s wrong.
Conspiracy Size
If Mark is right, then no one has been to outer space, and all of the astronauts are lying. Over 560 people have been in outer space, and so far, not one of them has come out saying that it’s all a lie.
If it is a lie, then everyone who has ever worked in astronomical telemetry is also a liar.
If Mark is right, then there are at least a handful of people at every one of the 72 national space agencies around the world who are conspiring to lie about the shape of the Earth.
If Mark is right, then NASA, AFSPC, RFSA, KCST and KARI, CNSA, ASA, The Iranian ISA and the Israeli ISA, CNES, ASI, HKAY, ESA, ISRO, JAXA, and the CCCP are all in cahoots to lie about their ability to launch rockets into outer space.
If Mark is Right, Elon Musk and SpaceX and Jeff Bezos and Blue Origin, Virgin Galactic, the ULA, Ad Astra, Masten, Intelsat, DARPA, Sierra Nevada Corp., Sea Launch, Nano Racks, Bigelow Aerospace, Aerojet Rocketdyne, One Web, Lockheed Martin, Rolls Royce, Boeing, etc., etc., etc., are also in cahoots.
As well as every commercial satellite company. Along with the people who build the engines that take equipment into outerspace, as well as agencies that oversee space flight such as the SIA, and companies that claim to use satellites like Verizon, AT&T, and Sprint, as well as all of the companies who map distance like Tom Tom, and Garmin, and Google, Microsoft, Amazon and Apple, as well as every GPS provider, and every president since the beginning of NASA, and every shipman who patrols Antarctica, and every explorer who has traversed Antarctica, and every shipping company who delivers packages south of the Equator, and every human who uses Maps south of the Equator is wrong… or Mark is wrong.
At some point you really have to admire the gall it takes for Mark to say with such confidence, “I’m right, trust me. Trust me, and not those ten thousand other people and organizations who say I’m wrong. Trust me.