Well, New Earth, If you're asking me if I see the futility of demanding evidence to substantiate faith-based claims, then of course...this is self-evident. But I'm guessing that most contemporary proponents of FET are laboring under the delusion that their model relies on precisely the opposite of faith; indeed, they ironically accuse others of blind faith. And, in the case of Tom at least, the philosophy seems to be driven by some kind of solipsistic "If I haven't personally verified the experiment it is false" mindset, which has some pretty major drawbacks.
Anyway, none of that is immediately relevant to the OP. Is there any meaningful way for an airplane to ascertain the shape of the world with a simple latitudinal circumnavigation, given the models at hand? It doesn't seem like it to me.
Vhu, I think the problem with your visualization is that you're rendering the FET's model as a simple Euclidean disc in which you would have to constantly bank as you circumnavigate, as if you were simply flying in a circle over land. But this is not the case, their model utilizes curved space such that, if I'm not mistaken...the plane does actually fly in a straight line, but its path through space will still curve about in a circle when you look down on a flat representation of the model.
Incidentally, the same principle applies to RET, if you look at a "straight trip" from one point to another on a flat map, the path will be curved. But don't even try to ask about the convoluted nature of FET's world geometry.