This is why the Flat Earth Society is the greatest free thinking organization on earth. The movement questions the unquestionable and challenges the unchallenged.
Oh please.
You declare the earth being flat an "obvious truth". Your basis for declaring it such is not stated, you seem to think the horizon appearing flat is proof but...well, it isn't.
Open a paint package and make a new image 10000x10000 pixels, zoom out so you can see the whole thing and draw a circle so it fills most of the image. Then zoom in to the image and note how the top is flat for quite a few pixels - when I did it, it was over 100. A big enough curve and a straight line are not distinguishable simply because our visual acuity is only so good. I really shouldn't have to explain this.
Anyway, having arrived at the conclusion of the flat earth being "obvious" you then do basically nothing to test that - I guess if you regard it as obvious then you don't feel the need to. You claim to be all about empirical evidence and yet you do pretty much nothing to collect any - I've suggested some experiments you could do to test your model, you've ignored all of them
And all the evidence which shows you to be incorrect is just ignored, wilfully misunderstood or just flat out denied. This doesn't make you a "free thinker". It's not thinking at all, it's just denial. You can do that about anything, it's easy to prove yourself right about something if you ignore all the evidence showing you to be wrong.