In a certain world there is a ruler who runs a very powerful country with an iron fist. A faction of oppositionists has been giving her lip and has made some mean comments implying she brings the country dishonor due to not being chaste.

She wishes to punish those remarks by enacting a certain song in a literal manner over the opposition's headquarters. An amount of young adult men from the opposition is to be defrenestrated from cargo airplanes while The Weather Girls' It's Raining Men is broadcast on all TV and radio stations.

Question: Assuming the lads are dropped from 10 km up, over an area of five acres and for five minutes, how many men would she need to drop in order for their blood to cover the streets and form puddles as much as the water from a light rain would over the same area and span? And how spread apart should they be?


  • Each body splashes half of their blood around upon impact and the blokes average at 70kg in weight;

  • She has a large enough fleet of planes (and as many men as she needs) to do it;

  • By light rain I mean small, shallow puddles on the asphalt. Also, if it were regular water instead of rain a simple umbrella would be enough to keep someone mostly dry.

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    $\begingroup$ This is disturbing in so many ways . . . $\endgroup$ Jul 8, 2018 at 17:00
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    $\begingroup$ I love this question, awesomely macabre and wonderfully gory but you do appreciate that depending on the surface impacted individual bodies are going to impart a lot more or less blood to more or less of their surrounds right? $\endgroup$
    – Ash
    Jul 8, 2018 at 17:02
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    $\begingroup$ Time to break out the turbulence equations. Anyone know the viscosity of a flow of ‘men’? $\endgroup$
    – Joe Bloggs
    Jul 8, 2018 at 17:22
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    $\begingroup$ I think this is too close to real world atrocities to be a decent worldbuilding question $\endgroup$
    – L.Dutch
    Jul 8, 2018 at 18:44
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    $\begingroup$ Why so high? 10km is much higher than necessary, and would complicate things without providing much advantage. A falling human body reaches terminal velocity at around 500 meters or so. beyond that, they will not fall any faster. At 10km, the crew would need supplemental oxygen. Plus, it would be a lot easier to hit the target region with precision from a lower altitude. Also, if they kept the altitude lower, they could enhance the terror effect by blaring the music directly from speakers mounted on the aircraft. (think Apocalypse Now) $\endgroup$ Jul 8, 2018 at 21:50

1 Answer 1


The scrap paper math goes like this:

$5$ acres is $20234.3$ square meters, rainfall is reckoned in $mm/mm^2$, you're describing what I think is roughly $2.5mm$ of rain so that's about $50585750000mm^3$ of total liquids, (not accounting for any effective area reduction due to the bodies lying around afterwards). The average human has 5 litres of blood, at half value, per your premise that's $2500ml$ meaning you'd need to drop about $20240$ men to make sure you get the desired saturation, roughly one per square meter across the entire target zone.

Do check my numbers, I'm not at all sure they're completely correct.

It would probably be worth attaching a small drag to the ankles of the men you're dropping to keep them head-down, this will boost their terminal velocity by about $100kmh^{-1}$, from around $190$ to $300+kmh^{-1}$, ensuring the best possible splash on impact. For best impact results your city should put the concrete in concrete jungle as well, bodies that hit asphalt sustain less damage and sink in rather than mashing so much on impact.

Note: You might get away with a far smaller number of men if the streets are crowded when you drop them.

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    $\begingroup$ This is disturbingly well thought out. $\endgroup$
    – ironduke97
    Jul 9, 2018 at 9:29
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    $\begingroup$ @Polan That's why I said "not accounting for any effective area reduction due to the bodies lying around afterwards" $\endgroup$
    – Ash
    Jul 9, 2018 at 10:08
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    $\begingroup$ If they're going fast enough when they land they might splash a little and some of the solids may end up a little more liquid, reducing the need for quite so many unfortunate captives. If humans don't reach the terminal velocity to splash you could strap some lead to them if you wish. $\endgroup$ Jul 9, 2018 at 11:51
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    $\begingroup$ @Ynneadwraith Humans only need an average of 450-500m of freefall to reach terminal velocity, from 10km up there's no doubt they'll hit at full speed, while I agree that there will almost certainly be secondary fluidisation the OP set an assumption of half blood volume for splash so I worked to those numbers. $\endgroup$
    – Ash
    Jul 9, 2018 at 11:57
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    $\begingroup$ Also, at ten miles up, they'd have to start dropping a couple minutes early to sync up with the song starting down on the ground. And has anyone considered missing the target thanks to wind resistance? $\endgroup$ Jul 9, 2018 at 15:34

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