I was just browsing the wiki, and I found something that seems a bit strange. It's short, so I'll quote it:
https://wiki.tfes.org/Universal_Acceleration#Terminal_VelocityIn the Round Earth model, terminal velocity happens when the acceleration due to gravity is equal to the acceleration due to drag. In the Flat Earth model, however, there are no balanced forces: terminal velocity happens when the upward acceleration of the person is equal to the upward acceleration of the Earth.
Q: If gravity does not exist, how does terminal velocity work?
A: When the acceleration of the person is equal to the acceleration of the Earth, the person has reached terminal velocity.
I'm having trouble putting this into the right words here... This section seems totally unnecessary. There's just nothing related to the shape of the Earth involved with terminal velocity. It's just not necessary to have this in there.
I'm trying to come up with a way to rebut this section without sounding like a total jerk, but... I just can't even.
Look... whether the downward force comes from Newton's law of gravity or GR or Universal Acceleration or "it's all relative density," it makes literally ZERO difference to the terminal velocity.
If you have questions about aerodynamic drag, I have some training (indoctrination) in that area. I can't think of any reason that drag is related to the shape of the Earth.