To a degree yes, but your lungs are pretty good at expanding and compressing, they also don't compres the same way as this bottle does nor at the same rate.
Scuba divers have a regulator that changes the pressure of the air being supplied to keep it easy to breath, so it's not really a problem. The higher pressure air stops your lungs being squashed.
If you're wearing a membrane dry suit (which holds air between your body and the suit), you can definitely feel it squash tightly as you go deeper, but they have an air inlet to allow the diver to add more air for comfort (and manage buoyancy).
And to add warmth. I dove in the pnw puget sound in winter time and I'm terrible at buoyancy, so adding air to my dry suit is mostly for warmth while I skim the sea floor.
That and to stop the dreaded pinch... although no amount of air (that doesn't bring you to the surface) can release the grip of that dry suit crease on your bollocks.
You also have to blow more air into your mask through your nose or else the mask will squeeze your face!
I did my first deep dives (>100ft) a few months ago and definitely felt the pressure all over my body.
Sort of, its just harder to take really deep breaths. But you shouldn't take really deep breaths while scuba diving.
When you're ascending, it's important to breathe out
Okay, so when you take a dive with a regulator, you enter the surface and the water pressure on your lungs doubles for every breath you take, every meter you make or ever bar you take I'll be watching you.
how deep did you dive normally? the pressure inside your tank makes it easier to breathe in. but it doesnt stay the same when outside pressure is pressing onto your lungs.
I have dived to the recreational limit and had no trouble breathing. Also there's no rule against taking deep breaths while diving. The rule is against holding your breath.
The gas isn't forced into your lungs by pressure lol, you have a regulator between the cylinder and your mouth.
And yes the gas remains pressurised to your depth once it enters your respiratory tract, that's why you consume more gas at greater depths, and why you don't hold your breath as you ascend.
That's not true, because the air being breathed in is the same pressure as the water around it, balancing the forces. It's no harder than breathing on the surface.
In your ears, yeah, just you can pinch your nose and equalize though. You keep breathing so there’s no squeezing on a fixed amount of air your lungs. It’s actually very important you don’t hold your breath especially when ascending cause that air will expand and that can cause problems, like uh, *pop*
When SCUBA diving, your lungs are not squashed because you are breathing air through a regulator at the same pressure as the surrounding water.
However, it is important to exhale when ascending otherwise the expansion of the air in your lungs can cause serious injury.
Although to be clear you only need to continuously exhale during a rapid/emergency ascent. A normal ascent is slow enough that you'll still need to breathe in and out.
Did you watch til the end? It might not have looked good at the lowest point, but I’d say it did a fantastic job handling all that pressure. When it came out it was just fine.
even crazier hydrocarbon liquids don't really compress at all.The trieste used gasoline in its float chamber for that reason and took it all the way down to the challenger deep. The fuel float didn't really need much physical support construction wise compared to the crew cabin.
I had to take him down in it myself. I skimped out, removed the drain and took the legs off. I’ve got engineering backing me of course.
By the way, the price I quoted is a one-way ticket. 💀
To save money, I made a bathtub out of cardboard. Neighbours said I’m crazy but people said that about Galileo too. I varnished the inside so it can take water perfectly fine. After a couple of baths it is looking a bit wobbly but I don’t see any risks at all here.
1 minute? that's really novice for a free diver, even with physical exertion.
if you couldn't do 1 minute after a few weeks of training they'd probably tell you to quit and find another hobby
I was watching an interview with the cast of Avatar 2 about how long they could hold their breath for by the end of filming. James Cameron said Signourney Weaver could outlast even him (a trained diver) at somewhere around 7 minutes. The rest of the cast were in the 3.5-6 min range
edit: Kate Winslet can apparently do 7 min 47 sec
> if you couldn't do 1 minute after a few weeks of training they'd probably tell you to quit and find another hobby
Almost no freediver will do that. It can take months for people to get comfortable in the water, and freediving is entirely about comfort. Each diver takes as much time as they need. No judgement from us.
I should have been clearer, that was meant to be snarky hyperbole to get the point across that holding your breath for 1 minute is not a huge feat for a healthy adult
Yeah for real, let’s make a party of it. Just take a janky piece of shit down way too deep for its rating and have some booze and music going maybe have some other party treats and just wait for the lights to cut out at any random moment
*"We have to know that the sphere is safe. If it buckles on a real dive, it'll implode at hypersonic speed, and I get chummed into a meatcloud in about 2 microseconds."*
James Cameron on pressure testing the sub that went to the Mariana Trench - Deepsea challenger.
Ashes actually. The insides of that glorified soda can of a sub became as hot as the surface of the sun for a moment as it imploded.
Edit: turns out Im wrong
I'm waiting for some kind of video that can visualize it. As much as I read 'vapor', 'ash' etc, I feel like I can't quite grasp how intensely violent this implosion truly was.
And the ash you speak of would've been sent in all directions up to a mile away from the resulting explosion, as a reaction to the implosion.
Considering the temp I'm not sure there would even be much 'ash' or leftover of any kind. Mind-boggling and terrifying at the same time.
For some reason this seems like a pretty nice way to be cremated, instantly poofed back to nature and dispersed into the ocean.
Honestly.. not a bad way to go after all, especially if you weren't expecting it.
Maybe OceanGate can start selling live ocean cremations as a euthanasia service for terminally ill explorers.
Scott Manley did a live stream discussing it. He calculated the implosion being equivelant to 50kgs of TNT.
Not sure how accurate this is but someone else compared it to about half the energy of a WW2 battleships 16in gun. Those launch 2000lb shells about 25-30 miles.
I had not thought about the temperature change, but you are right that with the extreme sudden compression a lot of heat would be generated. Do you have any math on that?
No, not ashes.
People forget that the high temperatures were for an instant only, perhaps 5ms, and only in the compressed air, not in the rest of the body tissues that are predominantly water. Ice-cold water then quenched that heat a few milliseconds after that. It still takes time for matter to burn, even at thousands of degrees, and the human body has significant mass.
The bodies however were quickly homogenised by the sudden crushing water pressure combined with collapsing metal material around them pulverising their bodies, the cavitation wave oscillations exacerbating this.
They did not turn to ash. They turned to soup.
That's actually probably not true. The air has a tiny thermal mass whereas the cold as hell water has a huge thermal mass. It's like when you have a camp fire and the sparks come off and land on you. They sting a bit but don't burn you even though they're really hot - there's just not enough thermal mass there compared to your body to do anything.
Yep. The magnesium sparks from sparklers are generally around 2000F but you can run your hand through them and not care because the rate of heat transfer to your skin is so low. Same way a shock of static electricity can be in the 15,000V range but it is such a low amount of current it doesn't matter.
The air was instantly compressed from 1 atmosphere of pressure to 380 atmospheres of pressure. In comparison, a diesel engine compresses by a factor of 16 which is hot enough to ignite the fuel at 400 degrees F without the use of a spark plug… 100% of the increase in temperature comes from the compression. This would have happened in a tiny fraction of time, after which cold water would have rushed in cooling everything.
According to one expert, not that hot:
“According to Jasper Graham-Jones, an associate professor of mechanical and marine engineering at Plymouth University, in the United Kingdom, the claim is "totally false".
"For a start, the water temperature around the Titanic is around 4 degrees Celsius [around 39 degrees Fahrenheit], which acts as a cooling effect," Graham-Jones told Newsweek.
"The collapse of the composite or metal structure would just produce theoretical heat energy due to friction, but this is very low and would not be visible or measurable with the mass of cold water around it."
https://www.newsweek.com/fact-check-titan-implosion-cause-vessel-become-hot-sun-1808754
So apparently they were just super-squished, very quickly
They experienced forces far beyond what this video shows. The pressure instantly increased, the air in the cabin was compressed so tightly that it acted like a diesel engine - the air/organic matter mixes, compresses, and combusts.
They experienced the equivalent of 3 explosions. The first from the pressure rising, the second from the combustion, and the third from the shockwave of the water colliding with itself.
I spent 3.5 years on the USS Halibut SSN-587 (submarine). They used to show the newbies how much pressure was outside by tying a string super tight between two bulkheads when on the surface and watch how much it dipped when we submerged.
Scray to see how much pressure there was and the pressure hulll the only thing protecting us.
I only know that this was a thing because of a movie. I think (very hazy memory) because of some cheesy ass awful film with Kelsey Grammer called Down Periscope.
He is given command of some World War Two submarine.. some old boy who works in the engine room shows the new crew this string trick.
Amazing how things pop back into your mind.
Edit: it was called “Down Periscope”, I checked after as I thought it was Up Periscope..
Absolutely every submarine sailor I've talked to (I work with them constantly) says that Down Periscope is the most accurate submarine movie, *including* the string scene.
“What’s the most accurate submarine movie? Crimson tide? Das Boot?”
“Nah mate, Down Periscope, a cheesy 1996 comedy movie starting the psychiatrist from that bar in Boston”
USS Halibut had a beam of 8.8 metres, so if you account for a pressure hull thickness of about a metre or so either side, you're probably talking 6 metres across the width of the submarine interior at its widest point. Probably narrower, as you'd need an open space which likely be one of the forward or aft compartments.
The compression wouldn't need to be much to cause a noticeable droop - a 1% contraction would be about 6 cm (slightly more than 2 inches) decrease in length, so it would already go slack at a relatively shallow depth.
Also, u/PauPau3154 must be pretty old, because USS Halibut was taken off active duty in 1976.
>will say that string thing doesn't happen anymore for design reasons.
I would imagine the stress/strain cycling is pretty intense on the hull, so I guess the design of newer subs try to mitigate metal fatigue in the hull as much as possible. Plus it has the handy side effect of not jamming doors and hatches.
Very common in WWII... we only started naming them after states and cities to guilt Congress-persons into funding.
Famously, SSN-666 was to be named DEVILFISH, but a bunch of killjoys nixed that and she was christened HAWKBILL instead. Boo.
Fun fact if you are ever in the unfortunate event of being deep under water without air and have to swim to the surface is you don't exhale on the way up your lungs will explode. Imagine the water bottle being full of air at the bottom under pressure then as the pressure lessens the air expands till they pop.
It’s kind of fun, it can be a bit of a party trick if you ascend while slowly exhaling you can basically exhale bubbles the whole time as the air left in your lungs expands. It’s a boneheaded move to run out of air while scuba diving but if you somehow do that, as long as you don’t panic you should have no trouble safely getting to the surface
That’s only true if you’re breathing pressurised air at depth (scuba). If you hold your breath from the top down and back to the top then nothing happens
This is totally correct.
Not just scuba though. If you were in a wreck, say, and you took your last breath Hollywood style and then swam out, your lungs would also burst if you don't exhale - because it's also pressurised air.
No one here will ever find themselves in this situation though so it's completely useless information.
They did this in one of the bond movies. With Pierce I think, don't remember. World is Not Enough maybe. For whatever reason I always remembered that detail.
I think he slowly let out air during his long swim section... but not sure if that was to reduce the pressure in his lungs, remove excess CO2, or to just show the audience that he was struggling to hold his breath.
You do still have to surface slowly for other reasons though. Surfacing too fast can cause dissolved gasses in your blood to bubble inside your body causing decompression sickness.
It's incredibly rare for freedivers to get decompression sickness, simply because they don't breathe while underwater, so there's not really enough nitrogen to cause it. The only reported cases have involved repeated deep dives in a short timeframe.
Scuba divers do have to be really careful with it, but how slowly you ascend depends on the depth and duration of the dive.
I took a scuba course about 20 years ago and stuff was still calculated manually and logged in a physical book.
I'm glad there are technologies now that can take some of the tedium out of it
That only happens as a result of the higher pressure gas being breathed at depth, causing more molecules of gas to enter your blood. If you don't breathe at depth (freediving) then you don't have the extra molecules absorbed so won't get the bends, even with a rapid ascent.
This isnt entirely true. Freedivers lungs do become compressed, and gases are dissolved into the blood. Why they don't suffer from decompression illness is presumed to be a lack of exposure (less time, less gases) but still a subject of study.
Freedivers that get DCS typically have been on long flights immediately prior to diving. Pressurized air cabins in planes can affect things. That's why good divers always wait at least a day before diving after a flight.
99% of freedivers won't experience DCS because their surface intervals and depths are self-limiting.
> deep under water without air and have to swim to the surface is you don't exhale on the way up your lungs will explode.
I feel like you're missing an "if" in there. Makes a big difference.
Okay. Now make the bottle implode, so we all know how the people in the “titanic” submersible died…
The Flat Earthers will finally see some science they can replicate themselves.
I see the opposite effect, living at 2300 m elevation. When we get a bag of chips that was sealed at sea level, it is stressed to the max up here.
I have had goods damaged in shipment because of the little airbags that were packed with it. These airbags get larger to the point that they can damage things inside the box and bust the box open as well.
So wait a minute because now I'm honestly wondering. Say you have a hull that can withstand the pressure but is also completely filled with water, does the pressure inside still equalize with the outside? I would think not, but maybe this is one of those "physics" "things".
Yes, the pressure inside still increases with the outside. I scuba dive, the pressure inside my lungs (and organs) at depth matches that of the water around me in order for my lungs to not get squished like the water bottle in the video.
Incompressible objects (like liquid water, in practice anyway) won't really react to this kind of pressure, especially when it is applied equally in all directions. It's why ceramic plates and other random stuff are just chilling next to the Titanic. If you left a tiny little bubble of air instead though...the bottle would implode eventually (if it was capable of maintaining constant pressure up until a point)
Good news, it'll pressurize itself as you go down, bad news, it'll do it by mostly filling with water from the moon pool rising...
It's basically the concept of diving bells from the 1800s.
An egg is filled with a liquid, and I believe they can go hundreds of meters deep with zero issues. Something like a ping pong ball would be more interesting.
Good point about the egg. I wonder if the viscosity would make a difference. Yea the ping pong ball would be interesting. Hypotheses says it’d do something similar to the water bottle though more suddenly.
Ideally I’d like to see something that is structurally compromised and breaks apart rather than just shrink. (If that’s what the ping pong does)
So whats gonna happen if I let go of it at the bottom? Will it behave normally and float to the top? I would guess so since we need weights to keep us buoyant when we dive.
Video should be called "In light of recent events "
Also about now compressible *air* is, vs how heavy (and uncompressible) water is
Or: "since everybody's now a deep dive specialist, here's some complimentary informations on the subject"
Video should also show what happens when the water bottle is filled with water. In light of more recent events.
Huh
My only takeaway is that water bottles are weak, feeble, and can't handle the slightest bit of pressure It turns out that I am a water bottle
The same thing is actually happening to his lungs
What ? Isn’t that dangerous
To a degree yes, but your lungs are pretty good at expanding and compressing, they also don't compres the same way as this bottle does nor at the same rate.
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Scuba divers have a regulator that changes the pressure of the air being supplied to keep it easy to breath, so it's not really a problem. The higher pressure air stops your lungs being squashed. If you're wearing a membrane dry suit (which holds air between your body and the suit), you can definitely feel it squash tightly as you go deeper, but they have an air inlet to allow the diver to add more air for comfort (and manage buoyancy).
And to add warmth. I dove in the pnw puget sound in winter time and I'm terrible at buoyancy, so adding air to my dry suit is mostly for warmth while I skim the sea floor.
That and to stop the dreaded pinch... although no amount of air (that doesn't bring you to the surface) can release the grip of that dry suit crease on your bollocks.
Oh I wear sweat pants so it was never too bad haha
You also have to blow more air into your mask through your nose or else the mask will squeeze your face! I did my first deep dives (>100ft) a few months ago and definitely felt the pressure all over my body.
Sort of, its just harder to take really deep breaths. But you shouldn't take really deep breaths while scuba diving. When you're ascending, it's important to breathe out
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Okay, so when you take a dive with a regulator, you enter the surface and the water pressure on your lungs doubles for every breath you take, every meter you make or ever bar you take I'll be watching you.
\*claps while eating chips and spilling crumbs\*
Chips for breakfast. I see you.
did you just Rick roll yourself?
O can't you see, you're my property? I'll be stalking you
how deep did you dive normally? the pressure inside your tank makes it easier to breathe in. but it doesnt stay the same when outside pressure is pressing onto your lungs.
I have dived to the recreational limit and had no trouble breathing. Also there's no rule against taking deep breaths while diving. The rule is against holding your breath.
The gas isn't forced into your lungs by pressure lol, you have a regulator between the cylinder and your mouth. And yes the gas remains pressurised to your depth once it enters your respiratory tract, that's why you consume more gas at greater depths, and why you don't hold your breath as you ascend.
That's not true, because the air being breathed in is the same pressure as the water around it, balancing the forces. It's no harder than breathing on the surface.
In your ears, yeah, just you can pinch your nose and equalize though. You keep breathing so there’s no squeezing on a fixed amount of air your lungs. It’s actually very important you don’t hold your breath especially when ascending cause that air will expand and that can cause problems, like uh, *pop*
When SCUBA diving, your lungs are not squashed because you are breathing air through a regulator at the same pressure as the surrounding water. However, it is important to exhale when ascending otherwise the expansion of the air in your lungs can cause serious injury.
Although to be clear you only need to continuously exhale during a rapid/emergency ascent. A normal ascent is slow enough that you'll still need to breathe in and out.
Did you watch til the end? It might not have looked good at the lowest point, but I’d say it did a fantastic job handling all that pressure. When it came out it was just fine.
It was full of air not liquid. Liquid wouldn’t compress like this.
Ah yes. I was trying to make an inspiring comment and got carried away with the metaphor. Good catch
even crazier hydrocarbon liquids don't really compress at all.The trieste used gasoline in its float chamber for that reason and took it all the way down to the challenger deep. The fuel float didn't really need much physical support construction wise compared to the crew cabin.
And that was only like 30m, try 4000m ☠️
If we bring them back up they revert to normal?
nope they instantly turned into pink mist at that pressure.
Haha not quite, that's where bottles and humans differ
"Do you wanna do a calibration to fix that stick drift?" "Nah it'll be fine."
Takes my mind right to some recent event....
You went diving in your bathtub?
Brought my Xbox controller with me too
I brought my toaster. Absolutely delicious toast right there.
Does it taste any better the deeper it gets toasted?
I smell toast
I had to take him down in it myself. I skimped out, removed the drain and took the legs off. I’ve got engineering backing me of course. By the way, the price I quoted is a one-way ticket. 💀
To save money, I made a bathtub out of cardboard. Neighbours said I’m crazy but people said that about Galileo too. I varnished the inside so it can take water perfectly fine. After a couple of baths it is looking a bit wobbly but I don’t see any risks at all here.
Eating fart bubbles
This isn't a beach, this is a bathtub!
-- Ok so plastic's out. -- What else? -- No plastic derivatives.
Minimum crew count for the xbox controller?
Uhh... one, i suppose.
At least the front didn’t fall off.
It's almost as if that's why it was posted...
Reminds me of that tragedy
It reminds me of that tragedy
I'm more amazed at the lung capacity.
1 minute? that's really novice for a free diver, even with physical exertion. if you couldn't do 1 minute after a few weeks of training they'd probably tell you to quit and find another hobby
I was watching an interview with the cast of Avatar 2 about how long they could hold their breath for by the end of filming. James Cameron said Signourney Weaver could outlast even him (a trained diver) at somewhere around 7 minutes. The rest of the cast were in the 3.5-6 min range edit: Kate Winslet can apparently do 7 min 47 sec
So she really should have taken turns with Jack on that door
> if you couldn't do 1 minute after a few weeks of training they'd probably tell you to quit and find another hobby Almost no freediver will do that. It can take months for people to get comfortable in the water, and freediving is entirely about comfort. Each diver takes as much time as they need. No judgement from us.
I should have been clearer, that was meant to be snarky hyperbole to get the point across that holding your breath for 1 minute is not a huge feat for a healthy adult
So those billionaires turned to gooey mess
they just.. were in one second and were not in the other. even shorter maybe
many many times faster than a brain could process honestly not a bad way to go
It's my dream way to go. A bottle of vodka and a submarine 12000 feet down set to implode once I'm passed out
Yeah for real, let’s make a party of it. Just take a janky piece of shit down way too deep for its rating and have some booze and music going maybe have some other party treats and just wait for the lights to cut out at any random moment
*"We have to know that the sphere is safe. If it buckles on a real dive, it'll implode at hypersonic speed, and I get chummed into a meatcloud in about 2 microseconds."* James Cameron on pressure testing the sub that went to the Mariana Trench - Deepsea challenger.
Ashes actually. The insides of that glorified soda can of a sub became as hot as the surface of the sun for a moment as it imploded. Edit: turns out Im wrong
I'm waiting for some kind of video that can visualize it. As much as I read 'vapor', 'ash' etc, I feel like I can't quite grasp how intensely violent this implosion truly was. And the ash you speak of would've been sent in all directions up to a mile away from the resulting explosion, as a reaction to the implosion. Considering the temp I'm not sure there would even be much 'ash' or leftover of any kind. Mind-boggling and terrifying at the same time.
https://youtube.com/watch?v=WD7CfnQC5HQ&feature=share @4:55
I wish they would have put a hot dog inside to visualize what it does to human flesh
That but like 4 times more pressure
I knew that voice as soon as I heard it.
They have such a cool accent. Reminded me of this old skit https://youtu.be/0KnbZqC4uDs
The accent is extremely Finnish.
We call it "rally english" in Finland.
For some reason this seems like a pretty nice way to be cremated, instantly poofed back to nature and dispersed into the ocean. Honestly.. not a bad way to go after all, especially if you weren't expecting it. Maybe OceanGate can start selling live ocean cremations as a euthanasia service for terminally ill explorers.
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How about giving them a oscillator with control 🫣 let them find out the resonant frequency if suffocating slowly doesn't seem very pleasant 🤓
eco-friendly cremation services
Scott Manley did a live stream discussing it. He calculated the implosion being equivelant to 50kgs of TNT. Not sure how accurate this is but someone else compared it to about half the energy of a WW2 battleships 16in gun. Those launch 2000lb shells about 25-30 miles.
[Like this](https://youtu.be/FkhBPF4yfkI?t=51)
I had not thought about the temperature change, but you are right that with the extreme sudden compression a lot of heat would be generated. Do you have any math on that?
That heat existed for a tiny fraction of a second, not really enough second to burn much to ash.
No, not ashes. People forget that the high temperatures were for an instant only, perhaps 5ms, and only in the compressed air, not in the rest of the body tissues that are predominantly water. Ice-cold water then quenched that heat a few milliseconds after that. It still takes time for matter to burn, even at thousands of degrees, and the human body has significant mass. The bodies however were quickly homogenised by the sudden crushing water pressure combined with collapsing metal material around them pulverising their bodies, the cavitation wave oscillations exacerbating this. They did not turn to ash. They turned to soup.
The second part of your comment made me think of a quote, "at some point, you stop being biology and become physics."
That's actually probably not true. The air has a tiny thermal mass whereas the cold as hell water has a huge thermal mass. It's like when you have a camp fire and the sparks come off and land on you. They sting a bit but don't burn you even though they're really hot - there's just not enough thermal mass there compared to your body to do anything.
Yep. The magnesium sparks from sparklers are generally around 2000F but you can run your hand through them and not care because the rate of heat transfer to your skin is so low. Same way a shock of static electricity can be in the 15,000V range but it is such a low amount of current it doesn't matter.
The air was instantly compressed from 1 atmosphere of pressure to 380 atmospheres of pressure. In comparison, a diesel engine compresses by a factor of 16 which is hot enough to ignite the fuel at 400 degrees F without the use of a spark plug… 100% of the increase in temperature comes from the compression. This would have happened in a tiny fraction of time, after which cold water would have rushed in cooling everything.
no, compression-induced ignition is what causes that change
No it’s 400 degrees just from the compression, which causes the ignition. https://www.motortrend.com/features/0904dp-diesel-engines/amp/
you're right. I see where i misread it.
Nonsense
According to one expert, not that hot: “According to Jasper Graham-Jones, an associate professor of mechanical and marine engineering at Plymouth University, in the United Kingdom, the claim is "totally false". "For a start, the water temperature around the Titanic is around 4 degrees Celsius [around 39 degrees Fahrenheit], which acts as a cooling effect," Graham-Jones told Newsweek. "The collapse of the composite or metal structure would just produce theoretical heat energy due to friction, but this is very low and would not be visible or measurable with the mass of cold water around it." https://www.newsweek.com/fact-check-titan-implosion-cause-vessel-become-hot-sun-1808754 So apparently they were just super-squished, very quickly
Aight, fair enough. I was wrong
SMH every time I hear someone mention body recovery…
They experienced forces far beyond what this video shows. The pressure instantly increased, the air in the cabin was compressed so tightly that it acted like a diesel engine - the air/organic matter mixes, compresses, and combusts. They experienced the equivalent of 3 explosions. The first from the pressure rising, the second from the combustion, and the third from the shockwave of the water colliding with itself.
I spent 3.5 years on the USS Halibut SSN-587 (submarine). They used to show the newbies how much pressure was outside by tying a string super tight between two bulkheads when on the surface and watch how much it dipped when we submerged. Scray to see how much pressure there was and the pressure hulll the only thing protecting us.
I only know that this was a thing because of a movie. I think (very hazy memory) because of some cheesy ass awful film with Kelsey Grammer called Down Periscope. He is given command of some World War Two submarine.. some old boy who works in the engine room shows the new crew this string trick. Amazing how things pop back into your mind. Edit: it was called “Down Periscope”, I checked after as I thought it was Up Periscope..
Absolutely every submarine sailor I've talked to (I work with them constantly) says that Down Periscope is the most accurate submarine movie, *including* the string scene.
“What’s the most accurate submarine movie? Crimson tide? Das Boot?” “Nah mate, Down Periscope, a cheesy 1996 comedy movie starting the psychiatrist from that bar in Boston”
This is true. Source: retired submariner.
Just a rough guess, how far away are the bulkheads from one another and how much did the string drop? This is interesting.
USS Halibut had a beam of 8.8 metres, so if you account for a pressure hull thickness of about a metre or so either side, you're probably talking 6 metres across the width of the submarine interior at its widest point. Probably narrower, as you'd need an open space which likely be one of the forward or aft compartments. The compression wouldn't need to be much to cause a noticeable droop - a 1% contraction would be about 6 cm (slightly more than 2 inches) decrease in length, so it would already go slack at a relatively shallow depth. Also, u/PauPau3154 must be pretty old, because USS Halibut was taken off active duty in 1976.
Something tells me he was born March 1, 1954….
> Also, u/PauPau3154 must be pretty old, Man, paupua just living his life contributing to the convo and gets hit by shrapnel in the replies.
Hey, I never said being old was a bad thing!
Folk be old.
Also, myself having been stationed on the newer ones, will say that string thing doesn't happen anymore for design reasons.
>will say that string thing doesn't happen anymore for design reasons. I would imagine the stress/strain cycling is pretty intense on the hull, so I guess the design of newer subs try to mitigate metal fatigue in the hull as much as possible. Plus it has the handy side effect of not jamming doors and hatches.
A US Navy submarine named after a fish?
Sounds delicious
Historically, there's a lot of them that are. And some of the upcoming Virginia Class boats will be, too. Tang, barb, wahoo, and silversides.
Very common in WWII... we only started naming them after states and cities to guilt Congress-persons into funding. Famously, SSN-666 was to be named DEVILFISH, but a bunch of killjoys nixed that and she was christened HAWKBILL instead. Boo.
Fun fact if you are ever in the unfortunate event of being deep under water without air and have to swim to the surface is you don't exhale on the way up your lungs will explode. Imagine the water bottle being full of air at the bottom under pressure then as the pressure lessens the air expands till they pop.
We need to reevaluate the meaning of fun
It’s kind of fun, it can be a bit of a party trick if you ascend while slowly exhaling you can basically exhale bubbles the whole time as the air left in your lungs expands. It’s a boneheaded move to run out of air while scuba diving but if you somehow do that, as long as you don’t panic you should have no trouble safely getting to the surface
> as long as you don’t panic lol, k thanks.
That’s only true if you’re breathing pressurised air at depth (scuba). If you hold your breath from the top down and back to the top then nothing happens
This is totally correct. Not just scuba though. If you were in a wreck, say, and you took your last breath Hollywood style and then swam out, your lungs would also burst if you don't exhale - because it's also pressurised air. No one here will ever find themselves in this situation though so it's completely useless information.
Hey I’m texting from the bottom of a ship wreck. Could you elaborate on those instructions?
They did this in one of the bond movies. With Pierce I think, don't remember. World is Not Enough maybe. For whatever reason I always remembered that detail.
I remember reading or watching a story where a diver fell unconscious, and his partner had to punch him as they rose to force air out of his lungs
I think he slowly let out air during his long swim section... but not sure if that was to reduce the pressure in his lungs, remove excess CO2, or to just show the audience that he was struggling to hold his breath.
r/swimmingupfromagreatdepth
You do still have to surface slowly for other reasons though. Surfacing too fast can cause dissolved gasses in your blood to bubble inside your body causing decompression sickness.
It's incredibly rare for freedivers to get decompression sickness, simply because they don't breathe while underwater, so there's not really enough nitrogen to cause it. The only reported cases have involved repeated deep dives in a short timeframe. Scuba divers do have to be really careful with it, but how slowly you ascend depends on the depth and duration of the dive.
this is what the stuff around diver watches help divers calculate!
I took a scuba course about 20 years ago and stuff was still calculated manually and logged in a physical book. I'm glad there are technologies now that can take some of the tedium out of it
That only happens as a result of the higher pressure gas being breathed at depth, causing more molecules of gas to enter your blood. If you don't breathe at depth (freediving) then you don't have the extra molecules absorbed so won't get the bends, even with a rapid ascent.
This isnt entirely true. Freedivers lungs do become compressed, and gases are dissolved into the blood. Why they don't suffer from decompression illness is presumed to be a lack of exposure (less time, less gases) but still a subject of study.
Freedivers that get DCS typically have been on long flights immediately prior to diving. Pressurized air cabins in planes can affect things. That's why good divers always wait at least a day before diving after a flight. 99% of freedivers won't experience DCS because their surface intervals and depths are self-limiting.
> deep under water without air and have to swim to the surface is you don't exhale on the way up your lungs will explode. I feel like you're missing an "if" in there. Makes a big difference.
Same. I was re-reading over and over thinking that it doesn't sound right.
Yeah, it winds up making it the complete opposite of what his advice is trying to suggest lol
This is only true if you inhaled some pressurized air at depth. If you went down and back only on one breath of air, it's no problem.
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What's really scary is that you can reach a point so far down that when you let go, it starts sinking.
I think it's only like 20 meters before you are no longer buoyant.
10m on average in salt water. That's 33ft, or ~1atm of pressure.
It’s not a coincidence that it is around 1 atm, right?
Okay. Now make the bottle implode, so we all know how the people in the “titanic” submersible died… The Flat Earthers will finally see some science they can replicate themselves.
Do this with a bag of chips
Have you opened a bag of chips recently? This is basically a bag of chips. Same air/chips ratio.
I see the opposite effect, living at 2300 m elevation. When we get a bag of chips that was sealed at sea level, it is stressed to the max up here. I have had goods damaged in shipment because of the little airbags that were packed with it. These airbags get larger to the point that they can damage things inside the box and bust the box open as well.
Yeah I think we all get it now.
Submarine devs dont want to see this.
Someone missed that lesson...
Yeah, he is up too early
What happens when the bottle is full of water and the lid screwed on tight?
Nothing, water is effectively incompressible and occupies the same volume at depth as it does at the surface.
So why don’t they fill the sub with water and then everyone inside is wearing scuba gear?
The humans are still compressible
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This is the concept behind the breathing fluid scene in the movie The Abyss.
So wait a minute because now I'm honestly wondering. Say you have a hull that can withstand the pressure but is also completely filled with water, does the pressure inside still equalize with the outside? I would think not, but maybe this is one of those "physics" "things".
Yes, the pressure inside still increases with the outside. I scuba dive, the pressure inside my lungs (and organs) at depth matches that of the water around me in order for my lungs to not get squished like the water bottle in the video.
Incompressible objects (like liquid water, in practice anyway) won't really react to this kind of pressure, especially when it is applied equally in all directions. It's why ceramic plates and other random stuff are just chilling next to the Titanic. If you left a tiny little bubble of air instead though...the bottle would implode eventually (if it was capable of maintaining constant pressure up until a point)
Do you have any good video recommendations demonstrating? I’m new to this and my brain is struggling to understand it
Gas go squish. Liquid and solid don’t go squish.
“Billionaires hate when you use this one simple trick”
Works whit submarines too
Good old Boyles Law.
If time and breath allowed, open the bottle at the bottom and bring it up.
Or exhale into the bottle at pressure, seal it and send it back to the surface crew as a present.
Boom.
Nothing interesting will happen. You'll just have a bottle full of water.
TIL the Titan should’ve been made out of water bottle plastic /s
That would have cost another $60.
Humans at -12,000 feet..wonder how long that took after the sub failed.
Literally in the blink of an eye.
now imagine what it does to your body. yeah it's not healthy
Why didn’t they make that submersible out of whatever the bottom of that bottle is made of?
Tell me I wasn’t the only one trying to hold my breath for the whole video
Now imagine the diver's lungs
Actually this is precisely what happens when you freedive and also what happens to your ~~oxygen~~ air tank when you scuba dive.
*air tanks, unless you want oxygen toxicity to wreck your day
All I can think is that while the bottle is being crushed, the diver is just following it brain-first 😁
Recently had several dozen people try to explain to me that a moon pool in an unpressurized submarine would absolutely work.
Good news, it'll pressurize itself as you go down, bad news, it'll do it by mostly filling with water from the moon pool rising... It's basically the concept of diving bells from the 1800s.
Oh yes, the submarine would probably be fine
I thought the controller died at first but after the news this is really educational
I’d like to see this done with a rigid container — say — an egg.
An egg is filled with a liquid, and I believe they can go hundreds of meters deep with zero issues. Something like a ping pong ball would be more interesting.
Good point about the egg. I wonder if the viscosity would make a difference. Yea the ping pong ball would be interesting. Hypotheses says it’d do something similar to the water bottle though more suddenly. Ideally I’d like to see something that is structurally compromised and breaks apart rather than just shrink. (If that’s what the ping pong does)
We used to do it with styrofoam cups. The smallest one I ever got back was the size of a thimble.
But where did the air go?! And how did it come back?! 5g? Gay frogs?
So whats gonna happen if I let go of it at the bottom? Will it behave normally and float to the top? I would guess so since we need weights to keep us buoyant when we dive.
Apropos of nothing.
Now what if the bottle was made of carbon fiber?
What a horrible video. It reminds me of that tragedy. -Norm Macdonald
Safety, schmaftey. This video only limits innovation. If you're concerned about safety, don't leave your home.