Tourist submersible visting the Titanic is missing 101

[ldeem]

Regarding liability in one of the videos the CEO talks about working with Boening on the pressure hull. I wonder how long before they try to distance themselves from this fiasco.

 

[Cool_Controls]

It has been reported that scuba cylinders were to be used as a last resort, can anyone speak to the ramifications of releasing that much extra gas into a confined space? Assuming 5 cylinders we talking something like 500 cubic feet of gas.

 

[TugboatEng]

Not quite the same pressures in an aircraft. Titanium is closer to carbon in potential than other metals, but there is still a difference in potential.

I wouldn't say this is true either. Aircraft experience cycles of wet and dry. While drying, the dissolved solids in the water concentrate, increasing conductivity which can accelerate the effects of galvanized corrosion.

Do remember that in this case if properly applied the epoxy seals the surfaces and only the very outermost edge is exposed for galvanic corrosion.

 

[TugboatEng]

It has been reported that scuba cylinders were to be used as a last resort, can anyone speak to the ramifications of releasing that much extra gas into a confined space? Assuming 5 cylinders we talking something like 500 cubic feet of gas.

It shouldn't be too much of a problem while in the craft. Humans are quite tolerant of hyperbaric conditions. After extraction, bends may become a complication. A little oxygen narcosis may be a good thing if the situation is unresolvable.

Supposedly they were only 45 minutes into a 2 hour descent. I don't know that they were near anything to snag on.

 

[CWB1]

Given the small composite hull and seeming lack of gear inside I'd have my doubts about any banging heard. I'd expect the hull to be fairly "dead" acoustically and the crew unlikely to have any large tools or other striking implements capable of generating the noise. After reading about the challenges encountered locating much larger previously lost subs I also suspect we may never find Titan.

From what I've read here and elsewhere I dont doubt that OceanGate's staff acted unethically wreckless, the real question is whether/not they broke the law and will anybody be held accountable.

Prayers to the families and hopes for preventing future disaster.

 

[electricpete]

The psychology of this voyage reminds me in some ways of climbing Mount Everest.... You put your life on the line and don't accomplish anything other than getting some excitement, cool photos, stories and bragging rights.

Although honestly I'd be a lot more impressed with the determination of someone who climbed Everest than someone who paid $250k for a ride.

No disrespect intended to those whose lives are at this moment in question. I just figured I'd spread my opinion around because... I just do that sometimes.

 

[JStephen]

I see "45 minutes" into descent, but everything else I've seen said 1:45.
Regardless, it looks like they lost contact before they reached bottom. They COULD have kept descending and looking anyway, and snagged on something. But actually snagging sounds unlikely from the details so far.
All kinds of things could have happened (electrical failure, fire, etc) but as long as the sub didn't flood or get snagged, it should have bobbed to the surface a couple of days ago, even if everyone was dead.
Hull collapse, failure of the porthole, or sudden leak sound like the most obvious things right now. A fairly small leak would be impossible to stop, and potentially hazardous to be near- and it might not take much water in there before it was unable to surface anyway. Or you might start surfacing immediately, but hit neutral buoyancy before you got the 2.5 miles up- then back down you'd go, faster and faster.
On the banging- the ends are titanium. Not sure what they'd have to bang with- belt buckles, water bottles, the emergency vice grips or whatever they had in there?
I saw the earlier comments on the gluing operations, and have no idea how critical that would be. I seem to recall that on the 3-piece bathyscaphe sphere, it was forged from steel but the three pieces were basically just held together by the exterior pressure.
This whole thing somewhat also reminds me of the guy that made the home-made rocket a couple of years ago- no doubt a more sophisticated approach, but still, not quite what you'd want to risk your life in.

 

[LittleInch]

Tug, all the reports I've seen said they lost contact after about 1 hr 45 which is why they thought it was probably on the bottom.

Not sure how the air or oxygen was replenished and waste air or co2 ejected from the capsule. I assume some sort of compressor or CO2 scrubber but that thing is so small there didn't seem to be any space for all that equipment and batteries etc.

I doubt they will ever find it.

To have a craft like that with no locator beacons or pingers or seemingly any emergency plan is close to criminal. And only having one sent down at a time is just as bad.

Actually quite amazing they managed to do 20 or whatever it was before something had gone wrong.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Cool_Controls]

The lack of a pinger is hard to believe, flight data recorders have them.

 

[waross]

They lost communication while still descending. I am thinking a battery failure.
Possibly sea water leaking into the battery compartment.
I suspect that when the communications went out, they also lost propulsion.
Depending on how fast the vessel dropped,it may have ruptured when it hit bottom.
That may have been kinder than sitting in the dark for four days waiting to die.


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

 

[Murph 9000]

It has been reported that scuba cylinders were to be used as a last resort, can anyone speak to the ramifications of releasing that much extra gas into a confined space? Assuming 5 cylinders we talking something like 500 cubic feet of gas.

If they were using standard high pressure SCUBA tanks, that would probably be 10l or 12l at 232 bar, so around 2320l to 2784l gas volume at 1 bar (per tank). Oversize 15l tanks are also commonly available, but there's not a lot of storage space inside this sub.

I think it's possible that they might have chosen rebreathers rather than standard SCUBA gear, as those would greatly reduce the volume of gas added to the closed environment. Rebreathers would also be relatively compact and lightweight for storage and handling, compared to normal SCUBA gear.

Not sure how the air or oxygen was replenished and waste air or co2 ejected from the capsule. I assume some sort of compressor or CO2 scrubber but that thing is so small there didn't seem to be any space for all that equipment and batteries etc.

I've seen reports saying that it was equipped with CO2 scrubbers, and there were additional passive type CO2 absorbers in the emergency supplies.

 

[Tomfh]

The psychology of this voyage reminds me in some ways of climbing Mount Everest.... You put your life on the line and don't accomplish anything other than getting some excitement, cool photos, stories and bragging rights.

Some people have an adventurous spirit. They see things differently. I follow some of the men and women who row and kayak across oceans. Long distance stuff. The Atlantic. The pacific. The Indian Ocean. The Tasman sea. It’s extremely hard, it takes people months, and is very dangerous. People die attempting it. They get a lot of abuse for risking their lives for what others see as a needless risk. For whatever reason they have to do this crazy stuff.

 

[JStephen]

"Some expeditions were delayed after OceanGate was forced to rebuild the Titan’s hull because it showed “cyclic fatigue” and wouldn’t be able to travel deep enough to reach the Titanic’s wreckage, according to a 2020 article by GeekWire, which interviewed the company’s CEO."

https://www.cnn.com/americas/live-news/titanic-missing-sub-oceangate-06-21-23/index.html

 

[dik]

from BBC:

https://www.bbc.com/news/science-environment-65977432

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

-Dik

 

[dik]

When I was in my 20s, I went from Vancouver to Victoria in an 18' outboard motor boat... Long trip... and my only concern was Orcas (It wasn't really a problem back then, but it appears to be one now). I used to be 10' tall and bulletproof back then... I've aged and am only slight attack resistant.

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

-Dik

 

[1503-44]

No pinger, locator buoy, or plan B? Well that's just because there is no way to be rescued. If they were on a sailboat, rescue 550mi out, maybe. When you're bolted in from the outside, forget the flare guns. Basically you're not even going to find anything inside 96h. How long did it take to find Titanic?

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[LittleInch]

Well clearly there are ways to be rescued as various ROVs etc are sailing to the location.

The Titanic didn't have a pinger....

But if it surfaced then finding it actually becomes harder as its a grey tub in a grey sea without a locator buoy.

Not even sure how many backup systems it has or the reliability of external equipment.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[Alistair_Heaton]

They have under 10 hours of O2 left

Soon it won't matte. It will be a much debated recovery. Hopefully though they will just comply with maritime norms and let them rest in peace where they are.

 

[1503-44]

It was never a realistic rescue operation.
Banging.. I have my doubts it was from this thing.
At that depth, its over before you know anything happened.
They're probably looking for something about the size of a 18" pipe.

--Einstein gave the same test to students every year. When asked why he would do something like that, "Because the answers had changed."

 

[Murph 9000]

It was never a realistic rescue operation.

There were some realistic scenarios which resulted in the sub being on the surface, either shortly after they encountered problems or quite a long time later (e.g. one of the fail safes was apparently a ballast release mechanism which essentially dissolved after sufficient period underwater). In that regard, the surface search and rescue operation was quite realistic.

Unfortunately, it's looking like implosion, flooding, or entanglement. Only entanglement would have some chance of rescue, but the associated search was always a problem in the available timescale.