.... The Scientific Method:  Observable. Testable. Repeatable. 

Nothing more.  Nothing less. 

This video represents true observation, without the distorted fish eye lens always used by NASA, Go Pro, and the like.  The horizon is perfectly level, no matter how high up you go. And perhaps even more importantly, and it is a biggie, notice how the horizon, rises to eye level, no matter how high you go. 

This would be impossible on a globe earth. 

Do you know what this means? It means you need not do any more research, because we just proved flat earth... horizon rising to eye level no matter how high you go, that's it.  That's all she wrote.  We don't even need the other thousand plus proofs we have, forget all that, we've got this. 

You have been set free.  Now all you need to do, is realize that.  You'd think it'd be easy, but it's probably not computing for you.  I know I had to hear it multiple times over a span of time, for this fact to set in, and grasp it.  Look back at this horizon/eye-level fact in a few weeks or months, after you fully realize the truth, and you'll see, you had all the proof you ever needed, right here, with this one simple observation.  It'll be fun.

And don't forget, you can launch your own high altitude device with a camera on it, and repeat this test for yourself, anyone can, and you'll get the same results.  And that, ladies and gentlemen, ain't no pseudoscience (please disregard one of the double negatives for that to make perfect sense... if it is perfection, you seek).