Titanic Tourist Submersible Goes Missing With Search Under Way (bbc.com) 152
A submersible craft used to take people to see the wreck of the Titanic has gone missing in the Atlantic Ocean with its crew on board, sparking a major search and rescue operation. From a report: Tour firm OceanGate, which runs $250,000-a-seat expeditions to the wreck, said it was exploring all options to get the crew back safely. It said government agencies and deep sea firms were helping the operation. The Titanic sank in 1912 and lies some 3,800m (12,500ft) beneath the waves. The missing craft is believed to be OceanGate's Titan submersible, a truck-sized sub that holds five people and usually dives with a four-day supply of oxygen. It is not known when contact with the craft was lost.
"Our entire focus is on the crewmembers in the submersible and their families," OceanGate said in a statement. "We are deeply thankful for the extensive assistance we have received from several government agencies and deep sea companies in our efforts to re-establish contact with the submersible," it added. The company bills the eight-day trip on its carbon-fibre submersible as a "chance to step outside of everyday life and discover something truly extraordinary." According to its website, one expedition is ongoing and two more have been planned for June 2024.
"Our entire focus is on the crewmembers in the submersible and their families," OceanGate said in a statement. "We are deeply thankful for the extensive assistance we have received from several government agencies and deep sea companies in our efforts to re-establish contact with the submersible," it added. The company bills the eight-day trip on its carbon-fibre submersible as a "chance to step outside of everyday life and discover something truly extraordinary." According to its website, one expedition is ongoing and two more have been planned for June 2024.
iceberg (Score:5, Funny)
First guess: it struck an iceberg? I heard they're plentiful at that spot of the sea.
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For reference, the wreck is at 41 43.5'N 49 56.8'W
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Not this century either lol.
I remember flying that way in the 90s and you'd always see ice there in the winter. I've flown a few times since same time of year and it's never there anymore. I've even flown more Northern routes and it's not even there anymore. You have to go pretty far North now to see sea ice and ice bergs now even in the depths of winter (other than the odd once in a while gigantic rogue ice berg that tears off and takes a few months to melt).
Pretty sure if the Titanic had sailed even in th
Re: iceberg (Score:2)
Re: iceberg (Score:2)
Not very likely that a nuclear submarine would be useful.
A nuclear submarine can go down to about 500m, the Titanic is at 3800m.
The water has a pressure of about 340 atmospheres at that depth. If there was a hull breach they'd be dead instantly.
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Volume is way too damn big.
Soviets had an attack sub with an estimated crush depth of 1500m using a dual-hull with the inner hull being made of titanium, giving better tensile strength per unit of mass then a pure-stainless vessel. Still nowhere near close enough, and it sank anyway.
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Re:iceberg (Score:5, Interesting)
Or, and this is just a wild guess, their novel craft which employs a carbon fiber hull wasn't up to withstanding the nearly three tons *per square inch* pressure it would encounter at the depth of the Titanic.
Older DSVs built for these depths, like Alvin, use solid metal pressure vessels with small holes for windows and hatches. Trieste used a steel sphere; Alvin has a titanium sphere. This thing appears to be two titanium hemispheres attached by a cylinder of carbon fiber. They talk a lot on their website about the innovative realtime hull health monitoring system, but I question whether you'd have time to react to a hull health alarm at depth.
The fact that they have lost contact with this thing for a full day is extremely ominous. These things are designed to self-rescue; they can drop ballast and ascend over the course of several hours. Even if they find this thing, if it can't self rescue it's not clear what they could do if it is thousands of meters under the surface. The best case would be that the crew is already on the surface but for some reason out of touch.
Re: iceberg (Score:2)
> âoeOur entire focus is on the crewmembers in the submersible ***and their families,***
They think they are likely dead too.
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This will be the mostly likely outcome. Maybe some good will come of this and trips down to the Titanic will be finally banned, then those people can rest in peace.
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Nah, they're probably alive and laughing about how all the people up top will be panicking, all because of a broken radio. LOL!
(How do they communicate anyway? Radio doesn't work well underwater)
When were they due back?
Re: iceberg (Score:2)
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I tend to think that given its last ping was directly over the titanic wreck site, if it sank or imploded they'd have seen some sign of it by now given we're more than 36 hours out. I mean that should be a pretty narrow search range to be within in either event. My bets are on they had a total loss of power, dropped their weights, slowly ascended over the span of several hours (possibly 10, according to one person) and drifted a fair distance away during that ascent, which leaves them bobbing along the surf
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One article said the sub has an emergency beacon (transmitter) on a flotation balloon that will self-release in many emergency scenarios, including loss of power.
There's some speculation that the sub got somehow caught in Titanic, or tangled in fishing nets, ropes, other debris.
Since they don't seem to have detected the emergency beacon yet, there's growing thought that it might have gotten caught in an ocean current, somehow pushed into Titanic, and can't get out.
I wasn't even aware of these subs or trips
Re: iceberg (Score:2)
I think they'd still be in contact if it was simply caught on something. And I kind of doubt the ideas about some piece of the Titanic somehow punctured it given how brittle it is at this point.
Re: iceberg (Score:2)
Banned by whom?
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Re:iceberg (Score:5, Informative)
Older DSVs built for these depths, like Alvin, use solid metal pressure vessels with small holes for windows and hatches.
You're very quick to discount material developments based solely on the fact something different was done in the past. The reality is carbon fibre can be incredibly strong. The ability to build a pressure vessel is nothing more than some careful engineering and a cost benefit analysis. We already use carbon fibre pressure vessels to store hydrogen at pressures twice of what you experience at 12800ft so the ability to withstand certain stresses is already well proven.
Glue and carbon was once discounted as not being suitable to make a car. Right until they absolutely dominated the hypercar industry.
Composites were once discounted as being too brittle to make aircraft wings. Right until they were proven as viable during the war, and subsequently found their way into the Dreamliner production years later.
Reflecting on the past as a defence against trying something new in the future is anti-development, and frankly doesn't belong on Slashdot.
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I'm less concerned with the carbon fiber per se but rather the pair of enormous seams.
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Storage vessel - internal pressure -> material must be strong in tension
Submersible - external pressure -> material must be strong in compression.
Very different scenarios.
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Again, engineering problems. The fact that a scenario is different doesn't magically mean you discount all R&D and material science and default to: "nah we've always made it out of steel, so that's all we'll ever be able to do." Which horse drawn carriage did you ride to work today? I mean the motorcar was written off on creation as utterly pointless and inferior to the horse in every aspect. Nothing can ever change right?
But in case you're interested in something more than "oh no this is different and
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You're very quick to discount material developments based solely on the fact something different was done in the past. The reality is carbon fibre can be incredibly strong. The ability to build a pressure vessel is nothing more than some careful engineering and a cost benefit analysis. We already use carbon fibre pressure vessels to store hydrogen at pressures twice of what you experience at 12800ft so the ability to withstand certain stresses is already well proven. ...
Reflecting on the past as a defence against trying something new in the future is anti-development, and frankly doesn't belong on Slashdot.
Just because nobody ever made a submarine out of papier-mache, doesn't mean it's not a good idea!
I'm not anit-development but if you see how sketchy the whole operation is, I think it's a good idea to be a bit skeptical. Especially when we're talking about sending tourists 4km underwater.
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Ohhhhhh...... Carbon Fiber.... I don't know about it in terms of submersible design but I do know of a rocket based example of how it can go wrong. Some years ago there was a rocket failure that was tracked down to a structural failure in a carbon fiber wrap for a solid rocket booster. Turns out that during testing they pushed it to flight loads plus a bit which is normal for steel pressure vessels. However carbon fiber, while very strong, is apparently more susceptible to performance degradation on suc
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And maybe another factor is that we've used and studied metals for, well, thousands of years, so we have a much better understanding of predictability of their performance. Also we've developed many ways to inspect for flaws, weakness, fatigue, etc. Seems like it would be more difficult to inspect carbon fiber for fiber breaks. I wonder if it could be done electrically. Mold in some electrodes and measure the conductivity and at some point if the conductivity has dropped too much (resistance went up), w
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Or, and this is just a wild guess, their novel craft which employs a carbon fiber hull wasn't up to withstanding the nearly three tons *per square inch* pressure it would encounter at the depth of the Titanic.
The Titan was deployed in 2021 and has already made several dives to the wreck. Previous dives were not for passengers though; the company was initially doing survey and imaging work. A lot of the recent pics and 3D scans of the Titanic that have been making the news lately, came from this vehicle.
While it's certainly possible the craft had a hull failure, it's not like this was an untested, first-time dive.
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That's true, but if IIRC their unmanned dives werejust to their rated depth. That doesn't establish any kind of margin of safety. When they rated Alivin for 6500m they pressure tested it to 8000m.
The other concern I have is the unique construction of this craft's pressure vessel -- if I understand correctly it's two titanium hemispheres bonded to a carbon fiber cylinder. The produces a large but light weight crew area. But it's a totally new way of doing this, and may have unanticipated failure modes.
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Probably not. Most vehicles have doors that open outwards simply because there's not a whole lot of space on the inside and the doors would get in the way when open.
For a plane, that means once the door is unlatched, the higher pressure inside will push it open. Though usually they swing open "against the wind", so will still need to be forced open much wider than needed to let the pressure out.
For a submarine that means the much higher pressure outside is pushing the door closed with enough pressure that
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For a plane, that means once the door is unlatched, the higher pressure inside will push it open. Though usually they swing open "against the wind", so will still need to be forced open much wider than needed to let the pressure out.
Most pressurized commercial aircraft use plug doors for most of their passenger doors; rather than pushing the door open, this pushes the door against the frame. While they usually do open outward (though there are exceptions, such as the 767 where they open upward), they either tilt inward or have some other mechanism by which they are larger than the frame.
As to what happens when non-plug-type doors become unlatched, Turkish Airlines Flight 981 and United Airlines Flight 811 serve as examples.
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First guess: it struck an iceberg? I heard they're plentiful at that spot of the sea.
Was it the sub's maiden voyage?
Re: iceberg (Score:3)
Isn't a hull failure or an electrical problem more likely?
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About equally likely, I'd say.
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There's very little life down there because it's cold, dark, very little food, and very little oxygen. Thermal vents and whale-falls are pretty much the only oasis down at those depths.
Submarine Rescue? (Score:2, Interesting)
This seems like it would be a trivial S&R mission for a military sub, although I'm not sure what you do once you find it. Do military subs have any facility to latch on to something? I would think that any such thing would be a bit of a liability.
Re: Submarine Rescue? (Score:5, Insightful)
Re: Submarine Rescue? (Score:5, Insightful)
Right you are.
It is 6000 PSI pressure at that depth. While this is a bit low for a water jet cutter that slice through steel plate (these start at 30,000 PSI) a leak of any kind would slice though most anything else. U.S. combat submarines collapse at depths a fraction of 12,000 ft. The USS Scorpion lies below hull collapse depth at 9000 ft. The U.S. only states that they can operate below 800 feet, but I once found a Russian language site that gave its max depth as 1800 ft.
The only remedy here is to refloat the submersible, one way or another.
There are very few submersibles in the entire world that operate at that depth. If you don't have one on hand at the site transporting one from some other place in the world in time out to the open ocean site to be useful would be a big problem.
I assume no tourists were on board, but a tourist would be exposed to similar risk on paying trips.
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This is a tourist sub. Passengers paid $250K per seat, so it's a rather wealthy subset of tourists.
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it is still dangerous, seat price does not matter when you get crushed by water.
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Unless you fault him for promoting the burning of fossil fuels.
If he didn't do it, someone else would.
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Do military subs have any facility to latch on to something?
The specially designed ones do. The ones you don't normally hear about. A similar one [hbs.edu] was proposed by the British when the Russian sub Kursk was damaged by exploding torpedoes. It was suggested to connect it to the Kursk so the remaining crew could be evacuated.
Private companies do have such subs used in underwater exploration, drilling, and so on.
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The USS Jimmy Carter is equipped for special underwater operations.
https://en.wikipedia.org/wiki/... [wikipedia.org]
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The crush depth of the Seawolf class was estimated as between 2400 and 3000 feet. You'd need something more specialized than that to go down to the ocean floor near the Titanic.
Re:Submarine Rescue? (Score:4, Informative)
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I was surprised to find that the DSRVs are limited to 5000 feet.
I suppose that makes sense, since a sub that was able to survive below that is unlikely, but it doesn't bode well for this situation.
Glomar Explorer was broken up in 2015.
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The interesting thing about the Kursk was it was 500 feet long, and sank in 330 feet of water. A third of it would stick out if it was vertical instead of horizontal at the bottom.
Never thought about it that way.
But yeah, the Kursk was ridiculously shallow compared to the Titanic.
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Do you mean subs like the Ohio class? They can't even get close to the depths they're talking about here. These depths require specialized submersibles built to withstand the crushing forces encountered down there. I hope they find these people but this is going to be a monumental task if the submersible somehow became unhooked from its tether.
Re:Submarine Rescue? (Score:5, Informative)
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There are several reasons not to do this, among others that a slight dip in power will drop the ballast.
But they do have multiple safety mechanisms that can be operated without electricity to do this kind of thing. If they have hull integrity and air, they should be able to get to the surface.
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Opposite way round. It is a safety system. If voltage drops, the ballist is released automatically. Like with trailer air brakes. Air pressure opens the brakes, loss of air pressure releases them to brake.
There may also be some sort of lever system to do the same without power,
But if the sub imploded, no people or integrity left to come up.
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Like with trailer air brakes.
The fact you had to be specific on the type and application of the brake shows that this is not as clear cut as being simply "a safety system". A lot of safety systems are not fail safe, e.g. your car brakes, or your air bags. Either of them suddenly triggering while you're on the highway is incredibly dangerous and could get you killed. Likewise suddenly rising uncontrolled from 12800ft can be fatal too so simply blowing ballast at that depth is not the kind of system you make fail safe.
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The fact you had to be specific on the type and application of the brake shows that this is not as clear cut as being simply "a safety system". A lot of safety systems are not fail safe, e.g. your car brakes, or your air bags.
Safety systems are engineered to a) likely failure modes, b) regulatory response (sometimes kneejerk) to specific incidents. Trailer brakes are related to _train_ brakes, and the failure mode train brakes are designed to accommodate is "coupling between cars breaks, back end of train starts rolling backwards down a hill towards the next train approaching on the same line". Car brakes don't have a similar failure mode; the safety system in car brakes is to have two hydraulic circuits so if one circuit fails,
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Likewise suddenly rising uncontrolled from 12800ft can be fatal too so simply blowing ballast at that depth is not the kind of system you make fail safe.
How exactly is it going to be potentially fatal, and how is it more dangerous than being stuck at 4km depth?
The inside is at roughly atmospheric pressure so people won't have decompression issues.
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Opposite way round. It is a safety system. If voltage drops, the ballist is released automatically. Like with trailer air brakes. Air pressure opens the brakes, loss of air pressure releases them to brake.
There may also be some sort of lever system to do the same without power,
But if the sub imploded, no people or integrity left to come up.
I assume it's not imploded. If it was, I expect at the least debris to be floating around (maybe not much, but still some).
And don't even simple life boats have small Emergency location beacons?
So presumably this will have something which activates when wet, and is buoyant. Unless it's tangled up in the wreckage and does not get to sea level.
https://en.wikipedia.org/wiki/... [wikipedia.org]
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Better to lose ballast and be alive than retain it and be dead.
Better not to lose ballast and die either. Rising to the surface from that depth is not risk free. Your life daily is government by systems which exist to keep you safe but are in an of themselves not failsafe. E.g. your car's breaks and airbags are purposefully not designed to be failsafe because the risk of triggering unintended rivals the risk of them not working.
Not every system needs to be fail safe, even incredibly critical safety systems. We have other ways and means of ensuring reliability without i
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I did the same thing as a kid, maybe 10, using a garden hose. Air exhaled out of my lungs in a big hurry. I was also terrified that I'd black out before reaching the surface, maybe 8 feet up. Learned many things that day.
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This seems like it would be a trivial S&R mission for a military sub, although I'm not sure what you do once you find it. Do military subs have any facility to latch on to something? I would think that any such thing would be a bit of a liability.
Military subs are designed to allow a rescue craft to attach.
Re:Submarine Rescue? (Score:5, Informative)
This is almost 4 kilometers below surface. Most military subs have crush depth of around 500-900m (actual depth is classified). Main exception is the Soviet titanium hull subs that had a crush depth of around 1500m, but those are no longer operational.
So if you tried to send a military sub to do this sort of operation, even if it's something like Jimmy Carter that actually has the mission module for releasing various mini-subs at operational depth, it would be crushed after getting about a third way down.
To go to depths described, you need specialized subs specifically built to withstand extreme pressures first and foremost, which results in them giving up most features that are desirable to militaries.
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https://en.wikipedia.org/wiki/... [wikipedia.org]
https://en.wikipedia.org/wiki/... [wikipedia.org]
Neither of them can get that deep.
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Both are retired, and both were meant for rescuing people from subs. There's no point trying to rescue people from imploded subs. They're dead already. So there was no point in making them able to go far beyond crush depth of military submarines.
Specialist submarines however can go far deeper than these military subs. Research submarines for example have gone all the way into the deepest parts of the planet's oceans in Mariana Trench. And nowadays, most of them are drone subs, because you don't have to deal
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They'd probably send a robotic/remote controlled submersible used for cable/pipeline repair at extreme depths. Man-rated subs that operate at these depths are rare and therefore not easily moved on site quickly.
Rescue will probably consist of attaching a lifting bag and picking up whatever is returned to the surface.
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Problem is that lifting something from that depth is... hard. And this is supposedly a sub that is meant to support five people for four days? It's going to be massive for a lifting bag that can even be inflated to a meaningful pressure at that depth.
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If the vehicle isn't intact, it no longer has any buoyancy. Even if you detach the ballast, it's still just going to sit there.
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Unlikely to be true. Most of vehicles of this kind are formed of multiple spheres that are interlinked by narrow channels that contain things like wiring. This is because sphere is naturally the most resistant structure to pressure.
If you lose a sphere that doesn't have people or life support systems/systems that power life support and because of this have a negative buoyancy even without ballast, there's great urgency to get them up before power or life support runs out.
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You don't have to search; the location is known (Score:3, Interesting)
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I bet you are a real joy at amusement park-related funerals.
Re:You don't have to search; the location is known (Score:5, Interesting)
People go on these trips for a sense of adventure and danger; much in the same way that I don't shed tears over folks who die on everest, I'm not going to here, either.
Not defending the mass-tourism to Mount Everest, here, but at least Mount Everest is a tourist destination primarily because it is some record holding point on Earth's surface, while the wreck of the Titanic is a tourist destination only because people died there in an accident. Which means that the currently missing group got an even more authentic experience of the original events than was advertised. Should they survive, the tour operator may be inclined to "charge extra" for the adventurous reenactment.
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Totally agree. The people who signed up for this knew about and accepted the risks. This isn't an amusement park ride.
I'm guessing there were some pretty clear waivers of liability signed for an adventure like this. I'd expect it to be the same with the nascent space tourism business. No matter how much fun money you have, shit still happens, especially if you tempt it enough.
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They aren't lost (Score:2)
They know exactly which direction in which to travel to get home. Up. I suspect that this submersible is equipped with numerous redundant self rescue systems (blow ballast tanks, drop fixed ballast, release signaling buoy, etc). That none appear to have been used yet does not bode well for the condition of the crew/passengers.
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They say a pinhole leak at that depth will result in a water stream that will cut through flesh instantly.
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Re:They aren't lost (Score:4, Informative)
They say a pinhole leak at that depth will result in a water stream that will cut through flesh instantly.
For reference [youtube.com]. This is larger than a pinhole stream, but you get the concept.
Also for reference, water cutting through 3 inches of aluminum [youtube.com].
Re:They aren't lost (Score:5, Interesting)
I suspect that this submersible is equipped with numerous redundant self rescue systems (blow ballast tanks, drop fixed ballast, release signaling buoy, etc).
Having read this article [cbsnews.com] published last year, I'd say it is very possible that there were no redundant self rescue systems.
Last broadcast (Score:5, Funny)
I'm King of th`^& g1~ NO CARRIER
Step out of everyday like (Score:4, Funny)
The company bills the eight-day trip on its carbon-fibre submersible as a "chance to step outside of everyday life
The company sure delivered: the rich tourists have a very real chance of stepping out of life period.
another submerged tourist attraction (Score:2)
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Hope They Had An Irony Lung (Score:2)
Breathe!
Re: Hope They Had An Irony Lung (Score:3)
More death enhances romance. (Score:2)
Fapping to dead rich people is quite the industry and nothing makes ships more interesting than a dramatic sinking. (Meanwhile museum ships go begging for funds.)
Death in the ocean profoundly titillates the average idiot so naturally their betters monetize that ghoulish craving. I thank the casualties for their contribution. A few deaths is of no technological importance but delicious clickbate (note appropriate spelling) so it makes Slashdot.
James Cameron (Score:2)
CBS News went down there a few years ago (Score:2)
there's one button inside and the sub is "controlled" with a video game controller
https://www.youtube.com/watch?v=29co_Hksk6o [youtube.com]
carbon fiber hull (Score:4, Interesting)
from the Oceangate [oceangate.com] website:
Through the innovative use of modern materials, Titan is lighter in weight and more cost efficient to mobilize than any other deep diving submersible...
Pressure Vessel Material: Carbon Fiber and Titanium
I would not trust my life to an innovative composite structure, unproven in a new design and application, subject to repeated use. Especially with maintenance and inspection procedures almost certainly derived from theoretical limits and not from experience and extensive destructive testing at scale.
"Carbon Fiber" means carbon-fiber bound in plastic resin. Sounds like maybe a rigid carbon fiber interior hull clad in titanium. All kinds of things to go wrong there that could be undetected; delimitation, corrosive resin breakdown, metal fatigue.
Anything could have gone wrong, but a good hunch is that the thing that failed is the complex, innovative and unproven design. Hull failure. That also explains why nobody has heard from the sub. In most other scenarios they jettison ballast, surface, and radio for help.
$250,000-a-seat expeditions? (Score:2)
Like the office (Score:2)
It's another place with no real reason for physical presence.
Accident? (Score:2)
It occurs to me that as a market is created for experiences like these and in orbit sabotage could become a serious concern
You're specifically catering to the ultra-wealthy - a group ripe with ego, enemies, and financially motivated opportunists. And you're taking small groups of them into extremely dangerous environments from which recovery from a serious failure is all but impossible, and forensics present serious challenges.
Kinda seems like a business model that would draw a huge target on its back.
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Woke Liberal Response: (Score:3, Funny)
"Corporations are still too cheap to buy enough lifeboats!"
Subbrief commentary (Score:3)
Sub brief (youtube #2 OSINT guy for everything submarine after H.I. Sutton) did a video with some basic research on the sub itself, the company behind it and the CEO, and jesus fucking christ is it a horrifying example of stupidity.
https://www.youtube.com/watch?... [youtube.com]
"I don't want to hire subject matter experts on submarines because they're all 50-something white guys". Hires a bunch of straight out of college kids. Goes to be the test pilot of the contraption. Removes the audio link to surface because he was bothered by surface support vessel constantly asking for update, which spoiled his enjoyment of the dive. First test dive to actual operational depth... with guests on board. Just to pick a few things out of many listed in the video.
This is just such an amazing clusterfuck.
Re:2.4 miles isn't a lot (Score:4, Informative)
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Bleeding edge costs. Popular stuff, scientists and engineers and businessmen work to bring down the cost until your stank ass can afford it.