Talk:TB-xx8vj Flerf/bevvite ?

"37,000 feet up requires a horizontal reference plane (flat earth)."

No, it just needs a local direction of down. 37 000 feet up means "37 000 feet above the point that is my GP"

"Level is a horizontal plane with no point higher than another"

Well, we can define height as distance of the center of a sphere.

But your lack of understanding of the meaning of "level" worse than that.

Level in general defines a surface of equal energy level. We have voltage levels, pressure levels, temperature levels, sound levels, none of which are flat or horizontal by nature, quite the contrary usually.

And we have gravitational level, or surfaces of same potential energy. As the predominant gravity source in or daily life is Earth itself gravity levels are basically closed 3d surfaces around the center of gravity of Earth. And as Earth is way larger than the limit of hydrostratic equilibrium it is an almost perfect sphere around its center of gravity. So gravity levels are pretty much spherical, too.

Only on small scales level can also be considered approximately flat.

A horizontal plane on the other hand is a tangential plane that on a perfectly round Earth would only touch it at one single point, with the rest of said plane getting higher and higher above the surface the further away from that special point you are.

"The horizon has 0 slope. Horizontal is parallel to the plane of the horizon at right angles to vertical."

Nope, and it is rather easily measurably not so. We e.g. would not have a need for dip correction tables in nautical almanacs if that were the case.

"It's really weird that you keep asking me about tides when I have not made any claims about tides."

And I wonder why you are bringing up tides here all of a sudden?

"A 24-hour sun in Antarctica doesn't have anything to do with the ground being measured flat. Just another red herring."

So then show us a flat earth model that can explain a 24 hour sun in Antarctica. How can the sun be seen from all places on the outer rim at the same time while the center is in complete darkness?

And no, the ground is not being measured flat. Not at all. No surveyor will agree with you on that. I'm not a professional surveyor myself, but I know quite a few and have been invited as speaker to a few of their conferences.