Sub lost contact over Titanic

JOhnH said:
The CEO of OceanGate, which is operating the missing Titanic tourist submarine, explains that the company didn’t want to hire any experienced “50 year old white guys” because they weren’t “inspirational.”
https://twitter.com/stillgray/status/1671372833979785217
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The general gist is there, but "didn't want to hire any" is not what he said. You can even look at the board and leadership pages on their website to see that's not remotely true (they are virtually all white men in their 50s)
 
At the risk of sounding ignorant, I am a bit surprised that the submersible wasn't tethered to the surface ship. 12k ft may be long, but tethered ballons have flown at higher altitudes. With a submersible, couldn't the tether supply air, water and communications?
 
JOhnH said:
The CEO of OceanGate, which is operating the missing Titanic tourist submarine, explains that the company didn’t want to hire any experienced “50 year old white guys” because they weren’t “inspirational.”
https://twitter.com/stillgray/status/1671372833979785217
Click to expand...

This venture kind of reminds me of the design approach Rutan and team took on SpaceShipOne/Two.

The ping pong ball on a string for the attitude / gravity indicator.

The wine cork in the fuselage hole to equalize cabin pressure.

The solid rubber fueled rocket motor, wound with a wire, to signal if the case burned through -- shutting off the O2 oxidizer supply and killing the engine.

The simple feather release mechanism mechanical handle that ended up destroying SpaceShipTwo when it was pulled prematurely.
 
Sounds racist & ageist. Seems in this line of work they would want the best minds & experience that could be found regardless of all the prejudices they harbor in their evil soul ...
 
Salty said:
I’m no expert, but I’d think that the sudden movement of water from outside the craft to inside the craft would be likely to do massive deformation of the hull that would collapse in a way that would be described as implosion. Much like the opposite when a container holding in pressure fails, it doesn’t simply allow the pressure to equalize, it typically destroys the container in a way we would describe as an explosion.

But you are probably technically correct.
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My view is as taught in navy sub school. It's mostly basic physics.

The 9" viewport failing isn't going to implode the people tank. What it will do is open a hole that floods around 175,000 gallons per minute of sea water to fill up the inner hull. That space will pretty much flood instantly and all the electronics are gone. But then, the pressure inside the tank is also instantly equalized with the pressure outside the tank. Implosion requires a pressure differential greater than the the hull strength, so it isn't happening. The hull is intact, just filled with water.

If you dive, you can see this. Empty an aluminum can and apply 2-3 layers of duct tape over the top. The can has just air in it, so when you take it to depth, you'll see it begin to bow in and then suddenly crush inward. This is implosion. Another example comes from a joke in Up Periscope with Kelsey Grammer. The old sub vet strung a rope across the compartment and showed it becoming loose as the boat went deep and the hull compressed a little - it's a real thing that happens. That's the pressure being applied outside and the metal shrinking minutely. Keep going down and it keeps compressing until the can gives way.

How does carbon fiber break under a uniform pressure? Or carbon fiber exposed to sunlight and sea water?

Call it a morbid professional fascination.
 
bflynn said:
How does carbon fiber break under a uniform pressure? Or carbon fiber exposed to sunlight and sea water?
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Or a carbon fiber - resin wrap that may not have been properly non-destructively tested for damage after multiple 6000 psi pressure / fatigue cycles?

In April, Ocean gate stated that Titan had completed at least 50 dives, including multiple at Titanic level pressures.
 
ElPaso Pilot said:
Interesting ballast release mechanism for the repurposed old pipes, if true:

pipes.png


"So here's the ballast. The journalist who went in it says you release it by getting everyone to sit on one side of the sub so it rolls enough for the pipes to fall off the shelf"

https://twitter.com/BirdTickler/status/1671002901064425472
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That's an elegantly simple solution for a mid-water ballast drop. Not dependent on anything electrical, or any through-hull mechanical connection.

On the other hand, I don't see it working if the submersible has settled onto the bottom sediments. Seems like that might also be a use case where you would want it to work.
 
GaryM said:
That's an elegantly simple solution for a mid-water ballast drop. Not dependent on anything electrical, or any through-hull mechanical connection.

On the other hand, I don't see it working if the submersible has settled onto the bottom sediments. Seems like that might also be a use case where you would want it to work.
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... or got wedged somewhere into the shipwreck debris.
 
GaryM said:
I think everyone realized by Monday that OceanGate is done. Whatever the ultimate outcome, they'll never put another manned submersible in the water.

I suspect it will be a long time before anyone runs another tourist dive to the Titanic.
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May also solve the debate over salvage of the wreck as I suspect there is a connection between Ocean Gate and RMS Titanic Inc (company that has been salvaging items from the wreck).

I think the whole thing is done. The lawsuits are going to be outrageous. Anyone remotely involved has to be crapping themselves right now.
 
Scrabo said:
Reports on media sites say


Rescuers Detect ‘Underwater Noise’ in Search Area and Redirect Efforts
The Coast Guard said in a brief statement on Twitter that some of the remote-operated vehicles involved in the search had been relocated in an attempt to determine the origin of the sounds
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If true that is unfortunate.

Also, whether true or not it unfortunate that they would even release such a statement.
 
sarangan said:
At the risk of sounding ignorant, I am a bit surprised that the submersible wasn't tethered to the surface ship. 12k ft may be long, but tethered ballons have flown at higher altitudes. With a submersible, couldn't the tether supply air, water and communications?
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Don’t even try to be rational about this. None of it makes any logical sense and the folks on board are nothing more than Darwin Award candidates.
 
A pinhole leak with 6000 psi behind it will make a water jet that can amputate body parts.

At that pressure, the flow through even a 1/16" hole is around 7 gallons per minute.

If the sub is full (or even half full) of water, I doubt it would be bouyant enough to rise to the surface even if all the ballast is ejected.
 
Hypothermia or air supply: news says 4 days of air. What’s the water temp wherever they are? News reports also say the hatch can only be opened from outside. My guess is that won’t matter, but one scenario would have them bobbing around on the surface and still be trapped inside.
 
sarangan said:
At the risk of sounding ignorant, I am a bit surprised that the submersible wasn't tethered to the surface ship. 12k ft may be long, but tethered ballons have flown at higher altitudes. With a submersible, couldn't the tether supply air, water and communications?
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The first unmanned submersibles to visit the Titanic 30 years ago were tethered. Nothing new.
 
On vacation and it’s raining. So a lot of
Time to read. I was reading about the sun James Cameron helped fund/build deep sea challenger.
https://en.m.wikipedia.org/wiki/Deepsea_Challenger

When you see what steps were taken to build this vehicle albeit different mission. Seems like they spared no expense. In fact that compressible foam they used allowed them to use all wired controls. No wireless stuff.
 
Half Fast said:
The first unmanned submersibles to visit the Titanic 30 years ago were tethered. Nothing new.
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Can/did the tether provide air and communications, or was it just a cable to possibly pull them back up?
 
One thing I've read in all the reporting, the sub's propulsion system has a maximum speed capability of 3 knots. However underwater currents can sometimes reach 10 knots and be highly unpredictable. How is that supposed to work?
 
The CEO in several of his videos talked about he 'took lessons from the aviation industry' but it seems like he forgot the first rule: Redundancyredundancy. All of the controls have to be wireless since I can find no perforations through the hull (during its construction) for controls. If the exterior wireless devices (assuming he used more than one transceiver) failed, the occupants would have no way to troubleshoot them. None. No way to reboot, re-bind, or do anything.
 
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Matthew said:
Hypothermia or air supply: news says 4 days of air. What’s the water temp wherever they are? News reports also say the hatch can only be opened from outside. My guess is that won’t matter, but one scenario would have them bobbing around on the surface and still be trapped inside.
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Roughly 34deg f.
 
2-Bit Speed said:
At the Titanic's depth? I doubt that. It's probably sub-zero.
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Unless the laws of physics are altered with pressure, 32 degrees is still freezing. Well 28 degrees for salt water. If it was sub zero, it would be one big block of ice.
 
2-Bit Speed said:
At the Titanic's depth? I doubt that. It's probably sub-zero.
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The bathypelagic zone. The bathypelagic zone takes its name from the fact that it is very deep (bathy=deep). It extends from 3000 feet to the bottom of the ocean and is very cold throughout. The temperature ranges from 5°C at 3000 feet to about 2° (36°F) at 12,000 feet.

Frankly, going hypothermic and simply falling asleep would have been merciful.
 
Greg Bockelman said:
Unless the laws of physics are altered with pressure, 32 degrees is still freezing. Well 28 degrees for salt water. If it was sub zero, it would be one big block of ice.
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Both salt and pressure lower water's freezing point. Regardless, hypothermia at 36* F probably looks very similar to hypothermia at 28* F.
 
Chip Sylverne said:
Frankly, going hypothermic and simply falling asleep would have been merciful.
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Other than perhaps the panic factor in some scenarios, few of them would be traumatic. Either over quickly or loss of o2 which is not painful.
 
Half Fast said:
Not Alvin. Argo. Argo was used to find the ship and it was an unmanned tethered ROV. Alvin came later.
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I thought you meant manned vehicles. I think side-scan sonar was used to find the ship.
 
Cap'n Jack said:
I thought you meant manned vehicles. I think side-scan sonar was used to find the ship.
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I believe they used the ROV to check out points of interest from the sonar. Check the links I posted above.

Regardless, the point I was trying to make was that tethering to a vehicle under 12,000' of water was done long ago and could have been done this time.
 
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