r/theydidthemath • u/Fizzerolli • 3d ago

[request] Assuming fresh powdery snow, how deep would it have to be for the paratrooper to survive, if possible?

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My son sent me this. My immediate thought based on nothing is that it’s unsurvivable regardless of the depth.

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u/SoylentRox 1✓ 3d ago

Note the skydiver doesn't have to be going terminal velocity. Potentially the drop could be from, say, 100 feet up, right at the stall speed of the 1940s Soviet transport aircraft used. At impact with the deep snow the skydiver will be traveling at ? m/s, or ? mph

Say it's 50-60 mph, for the Lisunov Li-2, a Soviet copy of the DC-3, which has a stall speed of 51 mph. Then at impact

v = sqrt[(v_0)^2 + 2gh]

Where:

  v₀ = initial speed (stall speed ≈ 27.7 m/s)
  g = 9.81 m/s² (gravitational acceleration)
  h = height (100 ft ≈ 30.5 m)

At impact, without drag, they will be traveling about 37 m/s or 83 mph.

I also tried a python script to model the speed vs time to take into account horizontal drag. I get

Impact results:

x: 61.19 m, y: -0.00 m

Horizontal speed: 18.97 m/s

Vertical speed: -21.59 m/s

Total speed: 28.74 m/s, which is ~64 mph

Then if the person, impacting at 64 mph, decelerates over 1m through the snow, they are subject to 42G of deceleration, which is on the edge of survivable.

About 5-10% of soldiers might survive this.

I am hoping the Soviets did experiments with dummies of the instrumented non living kind to test this before trying actual soldiers...

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u/Remarkable-Ask2288 3d ago

This is the Soviets we’re talking about. Of course they didn’t

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u/CrazyCatLady108 3d ago

considering there is no proof this ever happened, they probably didn't.

quick search brought up bunch of sites with no references and a mention of a 'myth' of a heroic squad jumping out of planes to stop a nazi tank column heading to moscow that started from a fiction book.

10

u/eyesotope86 3d ago

Gotta weigh that against the knowledge that the Soviets were (are) pretty resistant to acknowledging stupid things they did...

The CIA finally had to admit they were aiming for mind control, and that took nearly 50 years to admit, so one can only imagine the Russians are tight-lipped about really, really, really stupid ideas they messed with.

37

u/Spooder_guy_web 3d ago

Dawg the soviet archives are literally open, you can’t just say “the soviets were idiots and I think they’d do this, those dumb Russians”

-29

u/eyesotope86 3d ago

And if anyone has proven how trustworthy they can be, it's the Russians.

What do you do at the Kremlin, by the way?

29

u/SteelWheel_8609 3d ago

What do you do at the CIA? Both can play that game. It’s childish. 

-15

u/eyesotope86 3d ago

Except I used the CIA doing something stupid and keeping it hidden as an example of 'don't assume it didn't happen just because it's stupid'

So...

What's weird is the implication that I somehow called Russia more stupid, and the odd moral outrage at that.

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u/Bobzegreatest 3d ago

You're missing the point saying someone is working for russia because they disagree with you is childish

-5

u/eyesotope86 3d ago

Oh no! Not on this most dire, most serious subreddit!

How will I ever achieve my goals, now?

This sub is becoming a shitty parody of itself.

5

u/arbiter12 3d ago

The only parody here, is you.... You could have taken the L about 6 messages ago and been done.

-1

u/eyesotope86 3d ago

and been done

God knows r/theydidthemath is leaving scars on my psyche.

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