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Oceangate Statement, “We now believe that [all crew] have sadly been lost.”

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Re: Oceangate Statement, “We now believe that [all crew] have sadly been lost.”

#171

Post by salawat »

rightbyte wrote: post #148
aidenn0 wrote: post #98

Earlier quoted context omitted.

At 5800PSI, A leak with an area of 1/100th of a square inch would have 58 pounds of force behind the water coming in and a flow rate of about a half-a-gallon per second.

Sure I get that. A hole will be like a water cutter. I was thinking more like a screw with resistance along the threads such that the pressure goes from 5800 psi to say 20 psi at the last thread or whatever. Then you might get a stable leak.

At that point, you're counting on the material that thread is sunk into to be capable of withstanding that pressure without brittle fracture, and from the wrong side.

A screw is there to resist being pulled out. If water got to those screw threads as you posit, that'd basically be like reversing the forces to which that fastener was meant to resist. You go from "big chunk of material to hold in screw" to "little triangular threadforms trying to stay joined to the material around them in spite of 5800 psi trying to transit a pressure gradient insisting otherwise."

I'm not saying it's impossible, I'm just saying if I remotely thought it was possible to end up in that situation, I'd be going back to the drawing board to try to rule out that possibility. My brain just shows me visions of a screw turned into a bullet that barely gets slowed down going through a human body after threadforms crush like tortilla chips, a water cutter blasting through somebody into the opposite ablating a hole and causing a cascaded failure that then shortly thereafter becomes diesel thoomp.

If you'll excuse me, I'm abandoning this train of thought.

Re: Oceangate Statement, “We now believe that [all crew] have sadly been lost.”

#172

Post by epcoa »

rich_sasha wrote: post #149
alangibson wrote: post #36

Earlier quoted context omitted.

Pressure at that depth is about 5800 psi. Imagine 3 ton, 1 cubic inch cubes being dropped on every square inch of your body from every side all at once and you'll have your answer.

Hmm, but human body is mostly solids and liquids, not very compressible. Their lungs and airways, sure, would be compressed to nothing, but what of the rest of their bodies? Eg I'd imagine the poor souls on the Titanic next door are not crushed by the pressure, for the same reason. Or with scuba diving, deep scuba is complicated and dangerous for many reasons, but the pressure compressing the body is not one of them.

Think about why a parachute works. It’s the same concept.

Re: Oceangate Statement, “We now believe that [all crew] have sadly been lost.”

#173

Post by voisin »

411111111111111 wrote: post #152
getmeinrn wrote: post #75

Something I've learned over my life is not to automatically trust that someone has done or will do the right thing just because they stick their neck out. Sometimes they stick their neck out because they don't actually understand the risks and consequences, but they are pretending that they do. They're artificially signaling confidence. In this case, the CEO risking his life on this third(!) voyage means 1 of 2 possi…

The target of the adventure is also surprisingly ironic. The Titanic is one of the most notorious icons of human hubris. And these tourists died to the same.

Is it an icon of human hubris or simply a tragedy that they didn’t think could happen? I.e. did they take undue risks because of the belief that it was unsinkable? There was another boat not too far off when it sank so presumably they were taking normal risks and it was just an unfortunate way to learn that their belief that it was unsinkable was wrong.

Or are you referring to the insufficient number of lifeboats? I haven’t seen any evidence that other ships carried a larger number of lifeboats relative to their size.

Re: Oceangate Statement, “We now believe that [all crew] have sadly been lost.”

#175

Post by toomuchtodo »

voisin wrote: post #173
411111111111111 wrote: post #152

Earlier quoted context omitted.

The target of the adventure is also surprisingly ironic. The Titanic is one of the most notorious icons of human hubris. And these tourists died to the same.

Is it an icon of human hubris or simply a tragedy that they didn’t think could happen? I.e. did they take undue risks because of the belief that it was unsinkable? There was another boat not too far off when it sank so presumably they were taking normal risks and it was just an unfortunate way to learn that their belief that it was unsinkable was wrong. Or are you referring to the insufficient number of lifeboats? I…

> Is it an icon of human hubris or simply a tragedy that they didn’t think could happen?

https://www.bbc.com/future/article/20120402-the-myth-of-the-... (Titanic anniversary: The myth of the unsinkable ship)

"There is no danger that Titanic will sink. The boat is unsinkable and nothing but inconvenience will be suffered by the passengers." Phillip Franklin, White Star Line vice-president, 1912

Re: Oceangate Statement, “We now believe that [all crew] have sadly been lost.”

#176

Post by [deleted] »

jacquesm wrote: post #76
ilyt wrote: post #55

Earlier quoted context omitted.

I tried to find [1] how much pressure explosion of a grenade would cause. It would take a lot of grenades to get to 400 atmospheres... - [1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5514183/#:~:tex...

I wonder if you even could, given the fact that that stuff is trying to get away from each other you'd have to get the timing right to a ridiculous degree of precision.

[deleted]

Re: Oceangate Statement, “We now believe that [all crew] have sadly been lost.”

#178

Post by toofy »

ilyt wrote: post #105
WORMS_EAT_WORMS wrote: post #90

Almost as interesting as this story has been the comments online. Everyone, everywhere just parroting and re-parroting the same comments, attitude, pretending to understand the engineering with snippets from comments they’ve read, reactive talking points, etc… Very strange. Did anyone else feel like an alien following this story online?

And weird focus on that fucking gamepad that they were using, which was probably the least of engineering problems

i didn’t see the game pad as the cause, but an indicator of where they would cut corners.

it’s strange on its face to use a game controller when we’ve all spilled soda or water on one and watched it become useless and they’re taking this into… the ocean… and just to add insult to injury, playing on offbrand controllers always irritated me so to see them cut even further was super strange.

more than anything it is that combined with the stuff he bragged about buying from camper world—just a sign of strange corner cutting indicating their was likely more that we weren’t seeing.

Re: Oceangate Statement, “We now believe that [all crew] have sadly been lost.”

#179

Post by SV_BubbleTime »

hex4def6 wrote: post #140
SV_BubbleTime wrote: post #56

Earlier quoted context omitted.

Sounds like if the bells were found, but not the tube, we have the answer. If the window failed, I would expect to have none or one bell separated from the tube, but not both. I imagine the glass being shot inside the tube and the water jet would vaporize the people inside and maybe blow one bell off. If the tube failed, would expect both bells to be sitting on the ocean floor. I’m not a professional mechanical engin…

Agree, although if the bells are destroyed, that doesn't mean they were the failure mechanism either. It's entirely possible the tube collapsing would result in a huge water hammer effect on the bells, causing them to be shattered. It's going to be interesting to see to what level (if any), this gets root-caused. It's not trivial to do when stuff is miles down on the ocean floor. I assume there isn't a regulatory req…

The bells are titanium iirc, I wouldn’t think they would shatter. I thought the report is they were 100+ feet apart, it’s a crazy amount of force.

Re: Oceangate Statement, “We now believe that [all crew] have sadly been lost.”

#180

Post by amluto »

pfdietz wrote: post #142
f38zf5vdt wrote: post #63

Earlier quoted context omitted.

Probably combusted? At 400 atms their biomass would compress into a gelatinous hydrocarbon fat blob with the oxygen present, resulting in automatic combustion. The amount of compression their bodies would experience is an order of magnitude greater than a diesel engine cylinder. The explosion would immediately be quenched by the surrounding water and the only thing remaining of the occupants would be ash. This would…

Adiabatic compression of air to 400 bar increases the absolute temperature by about a factor of 5.5, which would be the temperature of a flame.

Water, fat, etc are not nearly as compressible as air, and the thermal mass of the air involved would be a couple orders of magnitude lower than everything else.

400 bar is (from some quick searching) fairly mild for industrial hydraulic systems, and hydraulic fluid doesn’t get especially hot while in use.

On the other hand, a leak in a pressurized hydraulic system is extremely dangerous if you’re around it due to the extreme velocity of ejected fluid.

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