Actually, I would guess the test failed for the same reason mirages are seen, depending on the time of day and a bunch of other things. With an air temperature profile that is cooler towards the ground, light will be bent around the Earth. That temperature gradient probably disappears when you go up 30 feet. That requires a tower at the midpoint
I wonder how the FE prople explain the fact that Moscow and California are about 12 hours apart for local noon but the Sun is not visible in one place when the other is having noon. On a flat Earth, the Sun is visible from all locations when it is "up".
There is also the problem that all celestial objects must be at an altitude of 4000 miles -- the Sun, the Moon and all the stars. That's easy to show with triangulation if you assume the Earth is flat. That makes the Sun 40 miles across. The Moon is also 40 miles across.
Triangulation becomes a big problem if you look at the direction of the Sun at sunset from two locations due north/south of each other. That measurement says that the Sun is in the same direction very nearly relative to the line joining the two sites.
And then there are all the problems related to satellites. I wonder how the FE fools explain GPS. Since I worked on a satellite-based program in the Air Force, I suppose Max thinks I'm part of the vast conspiracy and a liar and a deceiver.
So I have heard the FE bs floating around for awhile, but never paid it much attention. Max really believes the earth is flat? Never met the guy, but just based off what I know through social media, I would have given him more credit than that. Old Joe needs to get him on the air :grin:.