Tourist submersible visting the Titanic is missing 101

[XR250]

born into wealth,

Ironically, I was just thinking this the other day. No one named "Stockton Rush" ever grew up poor!

 

[Cool_Controls]

Another irony, for someone who disliked rules and regulations and claimed to want to be inspirational, it's likely he will be remembered for inspiring more rules and regulations.

 

[CWB1]

An FMEA is only as good as the ability of the team to fully assess the all forseeable risk factors and properly rate them and determine proper mitigation. We only know part of the story with the dismissal of Mr. Lochridge and the following litigation. Possibly, other members of the OceanGate team analyzed the FMEA differently and that is not unusual.

We also don't know if the perceived agism was real or simply bluster for publicity's sake. Tech entrepreneurs have a habit of making big claims about being able to revolutionize an industry by hiring brilliant outsiders to take a fresh look, which is usually pretty comical aside from the fact that many among the general public believe the nonsense. For all we know OG had a backroom of graybeards or outside safety auditors involved.

The sub may have sunk elsewhere but was US designed, flagged, and had operated with passengers in US waters so I expect US regulators will delve into both their engineering and operations practices to ensure they met US law. If OG's engineering dept didnt have thorough FMEAs or accepted risk needlessly I'd expect accountability.

 

[Denial]

Throughout this tragedy I have been trying to get my head around the amount of energy that people have been saying would be released by an implosion.[ ] It seemed much too high given the low compressibility of water.[ ] So last night I hunted out the values of a few key parameters and did a few rough-as-guts hand calculations, literally on the back of an envelope.[ ] The results astounded me.[ ] They suggested that the "potential energy of compression" released by the implosion would be equivalent to the gravitational potential energy that would be released if Titan had been hoisted to a height of about 600 metres then dropped onto a very solid block of concrete.[ ] My doodlings, slightly tidied up and spreadsheeted, are attached.

[Edit. A corrected version of the spreadsheet can be found below in my post of 26 Jun 23 21:30.]

 

[dik]

International waters? That's why I was wondering why Canada would be involved, other than the mothership taking off from Newfoundland.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[Cool_Controls]

Scott manley calculated the energy released by the implosion as being roughly equivalent to 50kg of TNT.
Link

 

[dragon6172]

International waters? That's why I was wondering why Canada would be involved, other than the mothership taking off from Newfoundland.

Mothership flagged/registered in Canada. I believe Maritime Law gives first jurisdiction to the country a ship is flagged in.

 

[Murph 9000]

Yes, the flag of the ship establishes primary jurisdiction. Additionally, the ship is owned by one of the First Nations of Canada. Canadian law applies on board the ship.

The UK MAIB are also claiming a seat at the table, due to the nationality of the passengers.

The US involvement comes from OceanGate being a US company. Their involvement in the SAR operation was automatic under SOLAS.

The various maritime investigation organisations are used to working together, so it shouldn't be contentious for them to work together.

 

[waross]

Would the energy be equivalent to the energy required to fill the sub's internal volume with air compressed to 400 atmospheres?
Possibly 400-1 atmospheres if you want to split 'airs.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[Cool_Controls]

I believe that was basically the calculation Scott used, internal volume of the sub multipled by the ambient pressure.

 

[waross]

Maybe the sign should be changed.
Energy released or energy absorbed?
Boom or Moob?
Either way, i wouldn't want to be close when that much energy is flying around.

--------------------
Ohm's law
Not just a good idea;
It's the LAW!

 

[Denial]

CoolControls.
I think I saw that kg of TNT figure somewhere, but it meant nothing to me as I was unable to visualise what it meant.[ ] That's why I set about trying to quantify it in terms of a vertical drop by a mass.

Waross.
No.[ ] I thought about it as filling the submersible's internal volume with WATER at ~400 bar.

[sub][ ]—————————————————————————————————[/sub]
[sup]Engineering mathematician/analyst.[ ] See my profile for more details.[/sup]

 

[Just Some Nerd]

Energy released or energy absorbed?

I view it as the latter - as you dive deeper, energy is stored as stresses in the hull, which release rapidly when said hull fails.

----------------------------------------------------------------------

Why yes, I do in fact have no idea what I'm talking about

 

[dik]

Thanks dragon and murph... I didn't know that it was registered in Canada.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[Tomfh]

They suggested that the "potential energy of compression" released by the implosion would be equivalent to the gravitational potential energy that would be released if Titan had been hoisted to a height of about 600 metres then dropped onto a very solid block of concrete.

Given the sub is essentially a vacuum bubble, wouldn’t the stored energy be roughly equal to a height above ground similar to the depth they descended to? Ie more like 3+ kilometres?

 

[Tomfh]

I view it as the latter - as you dive deeper, energy is stored as stresses in the hull, which release rapidly when said hull fails.

Most of the energy is the vacuum within the hull.

 

[TugboatEng]

I suspect some of the energy will dissipate during plastic deformation. That 50kg is a hot number to put on paper but not anywhere close to the real number.

 

[dik]

I suspect most of the energy was in the stored compression stresses in the carbonfibre when, being a brittle material, it 'suddenly failed and released all this stored energy in a split second.


I'm not sure at those stresses or load condition, there would be that much plastic deformation. Ever see one of the ceramic Corel dishes fail... a kazillion super sharp shards in a spit second... maybe something like that but without the super sharp components.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

 

[Tomfh]

The bulk of the energy is stored in the relative vacuum within the sub, not in the hull strain.

 

[dik]

I'm not so sure... that the reduced pressure in the interior would be that effective... it's mass would pale in comparison to the hull... I honestly don't know how the damage would be done... but life would be over in a split second, I suspect.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik