Beyond Titan - physics and the deep sea

[TokyoStories]

Continuing our crash course in all things deep-sea.

25 m is still deep enough for issues.
Can someone escape from that depth?

I guess they can recover it - but if they need to evacuate it, have they got an escape tube?

I suppose that's a general question - probably a YouTube video
What would happen if you drowned at the surface of the ocean and sank to the bottom?

I guess the air spaces in your body would fill with water - so there might be some compression?

It’s such a great teaching opportunity - I hope/expect science teachers all around the world have taken advantage of their students’ sudden interest.

Provided you don't simply drown, yes. People dive deeper than this both free diving and scuba and I believe submariners used to train to escape from their submarine in case of sinking.

If you’re near the surface when you drown, don’t you bob about on the surface because of all the air in your body? I’m just guessing, but have heard talk of “bloaters” before from my Navy (National Service only) Dad.

It’s such a great teaching opportunity - I hope/expect science teachers all around the world have taken advantage of their students’ sudden interest

I think it's more than just science teaching. It's about the human mind and how we ignore warnings etc.

Have people heard of Operation Market Garden? WW2 - A Bridge too Far. A plan to land troops to capture key bridges over the Rhine. There were lots of warnings etc and intelligence about how it could go wrong, poor decision making - and a sense of arrogance, hubris and gung ho towards it.

It went wrong. Because the warnings were ignored.

Learning from mistakes and analysing reasons why mistakes happen is so important.

Lots of bodies from the titanic were found floating. I think some of it is due to fat which is lighter.

One of our early lessons for swimming was to simply float, unfortunately for many due to body shapes it often means floating face down.

I think you initially sink as your lungs fill with water. Over time bacteria start to decay the body and produce CO2, which is what causes the bloat I believe. Like how the packaging of perishable food that's expired will bloat, for the same reason. Then people rise to the top.

I've just been browsing his other videos, they're great! Very surprised to see a 23 min video on endometriosis.

In the late 50's a young student who was caving in the Peak District died a horrendous death.

Google Neil Moss.
I will never understand the lure of caving, or God forbid river caving.

It was dreadful, wasn't it? That poor man; his poor wife.

At least the Dolphin divers and the Titan passengers died without even knowing they were in danger.

Oh wow! I didn't know that. Thanks to all who answered my question 😊

Just seen this - awful!

I can't understand what draws people to go underground.

This may have been mentioned already but following on from the talk about caving this is an interesting watch - https://m.youtube.com/watch?v=p24wxGo0otg

Thanks for that informative video @SirQuintusAureliusMaximus

I was wondering what might have happened to the Rubik's cube that the young man took with him. At first I thought just squashed down, but in the light of that video, it would have been superheated and maybe the plastic bits then were elongated and it broke into little blobs only to solidify in the cold water.

If it costs £250,000 each to take a trip down that deep on a jury-rigged cut-price low-safety sub, what would the ticket price be for one that's properly built, tested and certified safe?

Thanks for making this thread - it's been really interesting to read and agree I think there will be a lot of interest from kids / budding scientists in how it all works...

I wonder if this will be the end of vessels visiting the titanic now or whether work will start to build a safer one. Would anyone even go on it?!

Thank you for the thread, very interesting science

The submarines in the canary are a completely different story. They are regulated by government - have to have annual refits and inspections. The titan used 'innovating' and untested materials and were not regulated in the way commercial subs are.
Additionally commercial subs have to have surface boats following its (short journey typically) - depths are not deep (25 metres) so usually have visual as well as radio contact.
There is a reason most commercial submarines have been running for 40 years without incident

That Canaries submarine looks so much fun. In one of the pictures there was a whale skeleton. I think I’d have a stiff drink and get on with it, how could you not?

I don't like thinking about submarines in this context because it makes me think 'what if I wanted to get off like right NOW' and then makes me think well OMG an aeroplane is the same kind of thing - a metal tube that once you are going you can't get off.

I feel like if I go mentally too far into this space, I will never get on an aeroplane again - & flying doesn't really bother me.

Want to buy a commercial submarine?
Bored of having a yacht?

Commercial | Ocean Submarine

This does look quite cool actually

And there's more
10 most expensive commercial submarines in the world (scienceinfo.net)

It’s the pressure difference really. Atmospheric pressure at sea level is about 100,000 Pa

At 2 miles my pressure calculator which is essentially proportional to depth is coming out as a minimum of 31 000 000Pa that’s using a density of 1000 kg per m cubed but salt water is much denser. So a factor is 310 greater - that’s minimum then the collapsing can

Here's another video of an implosion of a steel tanker with a vacuum inside - bear in mind this is just normal air pressure that we live with every day doing this to a fucking tanker!! It's a metal solid tanker designed to hold contents safely

Atmospheric pressure is force per unit area exerted by an atmospheric column. The atm unit is roughly equivalent to the average sea level atmospheric pressure on Earth; that is, the Earth's atmospheric pressure at sea level is approximately 1 atm.

The pressure at the Titanic is 400 atmospheres. In other words 400 times greater than the pressure that you just saw squash a metal tanker in that way. Imagine that with 400 times more force.

The caption refers to "the destructive power of a vacuum" but that's not really the right way to look at it. It's not the vacuum causing it, it's the air pressure pressing into the vacuum. The air pressure does it.