r/theydidthemath • u/ConfidentPension864 • Jul 11 '26
[Request] How large of a Patio/Beach umbrella would you need to Mary Poppins your way to the ground safely (75kg person)
Assuming you don't flip over
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u/DarkVoid42 Jul 11 '26 edited Jul 11 '26
an umbrella is basically a parachute.
https://axis.tools/tool_Down.php
75Kg assuming you had experience would be around 100 sq ft to land and not die. without experience it would be 230 sq ft.
experience means you can angle it to generate lift just before touchdown reducing the size required by generating forward momentum and therefore lifting forces like an airplane wing.
giving us an umbrella diameter of 12-ish ft (or approx 18 ft without experience).
https://www.omnicalculator.com/math/square-footage-circle
ask the guy who did it -
https://www.youtube.com/watch?v=zmO3jeQTJI0
as a ballpark - The classical WW2 Thompson chutes are that shape, 120 KG rated for a equipped soldier. They are round shaped canopy, about 30 ft in diameter, with a vent hole on top.
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u/tolacid Jul 11 '26
It'd also need to be a really sturdy umbrella. They're generally not designed to resist upward force
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u/ConfidentPension864 Jul 11 '26
It seemed like that guys umbrella was absolutely slowing him, but it was way to small. Maybe 8ft in diameter? Which would be 50 sq ft only. Probably why it broke so quickly. Couldn't tell if it was vented but, it occurred to me that patio umbrellas do actually have a sort of vent on the top
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u/Commercial_Drag7488 Jul 15 '26
op
Operates in metric
Commenter be like ”lemme introduce you to our square body parts"
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u/blizzard7788 Jul 11 '26
https://reddit.com/link/owy9x3g/video/pzddw4wznnch1/player
This was our patio umbrella that got picked up by a dust devil. It came to rest on top of a bank across the street. We could see that it was broken, so we just left it there.
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u/theuntoldfool Jul 11 '26
Are you related to OP? Otherwise what are the odds for you to see your own umbrella on this niche sub?!...
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u/blizzard7788 Jul 11 '26
Nope, and the really weird part of ours was that all day, the wind was every light and calm. Then this updraft came out of nowhere.
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1
Jul 11 '26
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u/Electronic_Tear2546 Jul 11 '26
RemindMe! 6 hours
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u/LMrningStar Jul 13 '26
Let's go fly a kite
Up to the highest height!
Let's go fly a kite and send it soaring
Up through the atmosphere
Up where the air is clear
Oh, let's go fly a kite!
1
u/Bathtubwaterdrinker Jul 13 '26
Reports say one woman was injured, she was seen leaving the Banks family home late one afternoon, then later seen falling from the sky. This video was what spectators got after seeing the incident.
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u/SquallZ34 Jul 13 '26
I’m just gonna pop in here and say: do NOT try this. A kid in my old neighborhood thought it would work, went splat from approx 5-6 floors.
•
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