system
Given the following post, respond as if you're commenting on Reddit:
human
Since I have never seen it, I'm assuming it cant be done properly. Why do we not see people jumping out of airplanes with a super reinforced umbrella? Basically Mary Poppins style? What would happen is someone could build such a contraption and actually tried the jump?
gpt
An umbrella isn't nearly large enough to slow someone down sufficiently. If you try to upsize it, you'll soon run into problems with the size of the umbrella inside the aircraft (even when it's folded). In order to avoid that, you would have to come up with a less rigid structure, for example by connecting the surface sheet to the user by rope rather than solid stick. That way you could fit the whole package into a backpack.

But at that point you're just reinventing the parachute.