Is Earth Actually flat? Footage from over 80,000ft (no fish-eye)

At what height can we see the Earths curvature? This footage has been used because it is the only footage i can find at this height without fish eye lenses being used, as we can see at time the curvature is very noticeable but at times it almost appears to be flat with a straight horizon. At this height and large field of view should we not see more of a curve and does the cockpit glass alter what we see from certain angles? why doesn’t the horizon drop away on a sphere model as we ascend?

Post Author: hatefull