How fast did the people in it die?
Of course once the sub filled with water they would die instantly because it would reach insane pressures (300-400 ATM or 5800 PSI)
I don’t think anyone has any real data on the failure point, which is the needed info to know how long it would take to die. There has been lots of speculation that the carbon fiber used (rejected by Boeing as being out-of-spec) or the use of dissimilar materials each with different thermal expansion and contraction coefficients, to the “bubble window” being way under spec because the CEO didn’t want to pay for a proper spec one.
Without those we don’t know exactly how fast. We don’t know if they passengers had any indication of a problem (sounds?) or if it started leaking before it imploded or if it was an instant catastrophic failure.
I really don’t get this. The CEO knows that the window is so seriously under-speced, yet he still doesn’t hesitate to jump into the sub himself.
Specs aren’t a universal constant. They’re defined by humans. Expert humans, but humans. He must have thought he knew better than the experts. He was wrong, but I don’t think the lesson had time to sink in.
Here’s another way to think about it.
We can calculate what the change in volume of the chamber would be based on the difference in pressure when it collapsed.
Initially, at atmospheric pressure, the interior chamber contained about 5.6 cubic meters of volume. At the depth of the sub prior to implosion, the external pressure was about 3,000 psi. Once the walls failed, the interior volume was suddenly compressed from 5.6 cubic meters down to a miniscule 0.06 cubic meters.
Basically, the interior walls slammed in, compressing everything inside from the size of a small minivan down to the size of a very small fishtank
https://www.youtube.com/watch?v=Zz95_VvTxZM
You see the way this tank imploded?
What if the titan was the same implosion, albeit stronger/faster, but the way the edges/ends of the cylinder didnt really collapse, only the middle? What if you were sitting on the end parts?
This is all kinda blind speculation and there will be a formal report eventually, but as a general outline:
-When carbon fiber fails, it tends to fail spectacularly: completely and suddenly. So you can think of it not as “crushing a tin can” but more “smashing a glass lightbulb, but from all sides at once”.
-If we randomly assume they were halfway down (no idea on where they actually were but as a blind guess 50% is a good starting point) that’s about 200 atm of pressure. 1atm = ~15 psi, so thats about 3,000 psi. For comparison, a typical firehose is roughly 100 psi. And that can do serious damage to people: if a badly threaded cover pops off a charged hydrant, there is enough force behind that to break bones. If you were sitting next to the hydrant it’d hit you faster than you could react - you’d only know it after you’d been hit. The water outside the sub is at 30x that pressure.
-Lets assume just as an arbitrary approximation that in the first instant of the carbon fiber failing catastrophically, an area roughly equivalent to a 3ft diameter circle fails (it probably actually fails by buckling in a line then milliseconds later splitting and shattering, but we’re just approximating). This means that the water that flows through is pushed by 30x as much pressure as a firehose, and that pressure is coming in across 200 times as much area as a firehose (which are typically 2.5in diameter), so there are basically 200 of those 30x-power-firehoses coming through at once.
-A 2.5in firehose will do ~300 gpm. 6000 firehoses would be 1.8 million gpm. The internal volume of a 2m diameter/4m long cylinder is about 2,500 gal. That would be completely full of water in 0.001 seconds. Of course in reality water doesn’t hit full speed instantly, fluid flow is far more complex than just multiplying through like this, etc. But this just drives home that we’re talking very very small fractions of a second.
-Yes, compression = heating and when its super fast there isn’t much time for heat transfer so its adiabatic: wikipedia has an example under “adiabatic compression” for 10:1 compression going to about 500dec C (in an engine) and this is more like 200:1. But remember that air has low specific heat capacity and also doesn’t weigh much. The specific heat capacity of water (i.e. humans, plus those 6,000 firehoses worth of water) is ~4x that of air, and the density is ~1000x as much. So if you have equal volumes of air and person, and you heat the air by 4,000 deg C, that contains roughly enough energy to heat the person by 1 deg C. And also refer back to “there isn’t much time for heat transfer”. So chances that this actually matters beyond detailed physics calculations are slim.
Bottom line: completely obliterated by the force of so much water under so much pressure. By the time any water entered the sub it should have been over faster than a human could perceive. No explosions or incineration though, just force.
Also, common misconception: pressure alone doesn’t hurt you. You would not be directly hurt by spending time anywhere from the complete vacuum of space (0atm) to the challenger deep (1,000 atm). Obviously there are other little complications like you can’t breath in 0atm and that’ll kill you quickly, but the pressure itself won’t. Conversely at high pressures oxygen becomes toxic which isn’t great for staying alive, but the pressure itself isn’t the issue. Very rapid and therefore very violent pressure CHANGE, however, can and will kill you in many horrible ways.
This is a good example, it’s a hydrophone recording of a glass sphere imploding, the level of sound and echo should give you a good idea of the kind of forces we’re dealing with:
Less than 4 milliseconds. They didn’t feel a thing.
How did you get this number?
Do you think they died from the water rushing in and hitting them unconscious?
They died by being crushed with enough pressure such that the air inside the sub ignited ie compressed so much it essentially exploded. Death was instant.
I know a diesel engine works off compression, but it has a fuel. All fires must have oxygen, fuel, and heat. What fuel would they have in the titan to ignite?
Water contains oxygen. With enough heat that oxygen becomes free.
“Rushing” implies something like a wave. The thing crushed flat like the plastic tube it was, and would have done so too fast to even visually track.
If you were to slowly lower an open glass into the ocean, it would gradually fill with water. So i just think its the same with the sub, albeit faster?
Sure, but “faster” here means around the speed of sound, and that’s fundamentally a different thing from the playful streams we’re used to. The thing was waaay down there when it went.
If there was a tiny little hole somewhere that wasn’t getting larger, maybe it would slow down enough to just gradually fill the vessel. In that case, though, it would not have imploded. They found it in pieces and the US Navy heard the pop.
To add context here, it takes your brain somewhere around 100ms to detect and then another 250 to process pain. So 4ms is not only fast, it’s absurdly fast.
To get a sense of how fast it is, go ahead and stub your toe, the time it took to feel it is 100 times longer.
