I also believe there are far more edge cases to deal with: specifically the edge of the blades on the propellers. Whirling blades with an engine powerful enoug

I also believe there are far more edge cases to deal with: specifically the edge of the blades on the propellers. Whirling blades with an engine powerful enough to lift and transport a human plus cargo whizzing through downtown areas, and everyone owns one? It only makes sense in sci-fi movies.