Yeah probably. It's part of the Titanic's legacy now. It's also a weird story. It's an absolute freak accident and we had our hopes built up for a week only for them to have been for naught.
Yeah probably. It's part of the Titanic's legacy now. It's also a weird story. It's an absolute freak accident and we had our hopes built up for a week only for them to have been for naught.
Having watched the video recently, I think one of the main points is that it isn't really a freak accident in the sense of it being unlikely to happen. The video presents at least that they For...
Exemplary
Having watched the video recently, I think one of the main points is that it isn't really a freak accident in the sense of it being unlikely to happen.
The video presents at least that they
For the hull used materials with known but poorly understood fault modes affected by fatigue / stress cycles.
Ignored warnings from engineers about the construction specifically with respect to this.
Refused to do a safety classification of the construction according to regular practice for submarines (which would include fatigue testing).
Argued that in their construction it's impossible to make certain verification on the hull construction due to its thickness, so they will use a monitoring system instead.
(The above is from memory, so may be slight discrepancies - I do recommend watching the video as it goes through this in more detail than I can, including showing documentation such as articles and press statements.)
It may have been a freak accident in the sense that
it was unusual
it was high profile
the company did not expect it to happen
the media attention lasted for an extended period of time
but I think with the information as presented in the video it is a disservice to the engineering profession, best practices, and regulatory bodies that deal with safety to call this a freak accident.
EDIT: Just to add, this is not to say that with the information as presented this is definitely the underlying cause for the accident. Still, even if it isn't, it means the submersible was likely a tragedy waiting to happen.
To quote Hot Fuzz, accident implies that no one's to blame. A freak accident is completely unexpected. If a meteorite crashes into New York today and kills one person who happened to be standing...
To quote Hot Fuzz, accident implies that no one's to blame.
A freak accident is completely unexpected. If a meteorite crashes into New York today and kills one person who happened to be standing on a manhole cover three blocks from the impact - that's a freak accident.
If you take a highly experimental submarine underwater after refusing to test it to modern safety standards and end up killing everyone on board, that's negligent homicide... But since you were on board, negligent suicide as well.
I think that tragedy is probably the word to use. A completely preventable and unnecessary tragedy.
With some consideration, I would in daily parlance probably go for tragedy instead of accident. To me, that has less connotations on the likelihood, predictability, or culpability of the event I...
With some consideration, I would in daily parlance probably go for tragedy instead of accident. To me, that has less connotations on the likelihood, predictability, or culpability of the event
I think I would use disaster in a more engineering-focused discussion, but in layman's terms, to me, it carries a bit too much sense of magnitude to be well-suited. Mind, I'm not a native English speaker, so my intuition here may definitely be off.
I would argue similarly about catastrophe, to me it feels too grand in scope to be applicable.
It seems pretty obvious that the correct characterization of this event is "entirely predictable and predicted result of criminal negligence." The only remarkable thing about it is that the...
It seems pretty obvious that the correct characterization of this event is "entirely predictable and predicted result of criminal negligence." The only remarkable thing about it is that the perpetrator and a handful of of his cohort actually suffered the consequences of it - the much more common scenario is that a bunch of innocents suffer and the perpetrators get at most a slap on the wrist.
The whole situation also provides an interesting look into the mind of a wealthy businessman fully seduced by and absorbed into capitalist thinking. He so thoroughly had to convince others -...
The whole situation also provides an interesting look into the mind of a wealthy businessman fully seduced by and absorbed into capitalist thinking. He so thoroughly had to convince others - including the rest of his company and other wealthy businesspeople - of his merits in engineering, innovation, and entrepreneurship that he believed his own myth and utterly sabotaged his perspective. I think that it spells out the relevance of the old adage of never assigning blame to malice when stupidity will suffice, in a world where the inherent malice of greed is already lurking behind every decision.
I like "catastrophic failure". It doesn't imply whether it was avoidable or not, and the failure was on the part of both the materials and the company's strategy of cutting corners and ignoring...
I like "catastrophic failure". It doesn't imply whether it was avoidable or not, and the failure was on the part of both the materials and the company's strategy of cutting corners and ignoring warnings.
A quick google search shows that submarines have imploded before (and actually there’s quite a list of incidents since 2000 which I was surprised by). I think what made this such big news is that...
A quick google search shows that submarines have imploded before (and actually there’s quite a list of incidents since 2000 which I was surprised by). I think what made this such big news is that it was a private tourist trip. To my knowledge it’s a first in that sense, although I didn’t delve into the topic too deeply
Do you have a source? A quick search doesn't show any submersibles that imploded and no submarines where implosion was the cause of failure, just fires and explosions or leaks that made them sink...
Do you have a source? A quick search doesn't show any submersibles that imploded and no submarines where implosion was the cause of failure, just fires and explosions or leaks that made them sink below crushing depths.
They are pulling from the wikipedia, which is pretty easy to find. There were a lot of implosions in the 20th century, but the big one I know was the Thresher, which imploded during a deep diving...
They are pulling from the wikipedia, which is pretty easy to find. There were a lot of implosions in the 20th century, but the big one I know was the Thresher, which imploded during a deep diving test . . . in the North West Atlantic. But there were dozens, if not hundreds of subs that the primary cause of destruction was implosion during WWII and WWI, and that doesn't even get into the many many bathysphere implosions in the 60's and 70's (not an engineer, but a fluid dynamics guy . . . I find this shit fascinating), mainly from people building them in their backyards (you could buy the plans in Popular Mechanics) and then . . . just disappearing .
I would say in human history, a majority of the deep sea diving has resulted in implosions (watching footage from a ROV implode is something else, but it was meant to implode and had data loggers everywhere).
It's historical stuff generally (since geocities went down) not online. The Thresher is pretty well known though, it was the first US atomic sub that imploded do a depth test, but a lot of subs...
It's historical stuff generally (since geocities went down) not online. The Thresher is pretty well known though, it was the first US atomic sub that imploded do a depth test, but a lot of subs have "gone missing" (like the soviets lost somewhere between 2 and 15 subs . . . no one knows, and everyone that did know is dead).
Like, it's fuzzy math, we don't know that all these subs imploded, but . . . just take a look of the last 100 years, there are a lot of subs and submersibles "missing", not counting all the "off the books" subs (like narco subs) built in peoples backyards that . . . they just went out one weekend and never came back . . . like did they implode or did something else happen, we don't know but implosion is generally considered a leading cause.
I hear this stuff because I have a degree in a "related field" and made some friends when I was doing research at Scripps Oceanagraphy who I still talk to and keep up with the rumor mill. And a lot of it is the rumor mill, but if someone gets a ping on a hydrophone of an implosion happening at >300 feet (actually listening for whales) and then there is a search for a guy who went out in an "experimental" craft 2 days later . . . you can draw some conclusions . . . but if it's just some dude no one really makes a huge deal (like how many missing boats have you heard about this year . . . like in the last 10 years there has been a couple of hundred boats of normal people that just . . . go away, and most of us hear nothing about them).
In April 1963, one of the Navy's first nuclear submarines imploded off the New England coast, killing 129 people. Something caused the sub to sink beyond its rated depth until it was crushed under the pressure, says James Bryant, a retired submarine captain.
That one will probably be argued about in court. An ex-employee sued them because they refused to do this allegedly impossible verification and subsequently installed an audio monitoring system to...
the company did not expect it to happen
That one will probably be argued about in court. An ex-employee sued them because they refused to do this allegedly impossible verification and subsequently installed an audio monitoring system to listen for cracks. This is not only totally inappropriate for the type of failure carbon composites experience, but also on a previous dive someone reported hearing cracks and asked for this to be checked out. For some reason this didn't happen.
This about sums it up. It's not just a weird story, it's really quite extraordinary. As far as I'm aware this is the first time a submersible has actually imploded like this, not to mention...
This about sums it up. It's not just a weird story, it's really quite extraordinary. As far as I'm aware this is the first time a submersible has actually imploded like this, not to mention inventor of the submarine was on board, not to mention they are literally part of the grave of the freaking Titanic. This story is absolutely insane and although incredibly sad, also morbidly fascinating. We'll be hearing about this for years to come, and for good reason imo.
I've heard this said before, but reading it this time, for some reason, makes me envision a movie/story of ghosts "living" on the titanic wreck. Alone for 70+ years on the ocean floor, then they...
not to mention they are literally part of the grave of the freaking Titanic. This story is absolutely insane and although incredibly sad, also morbidly fascinating.
I've heard this said before, but reading it this time, for some reason, makes me envision a movie/story of ghosts "living" on the titanic wreck. Alone for 70+ years on the ocean floor, then they start seeing submersibles, and now there are 5 new ghosts from the future.
There were "probably" a few dozen bathysphere implosions in the 60's and 70's that we just don't know about (this is based on urban folklore at Scripps in the late 90's early 2000's). But I know...
There were "probably" a few dozen bathysphere implosions in the 60's and 70's that we just don't know about (this is based on urban folklore at Scripps in the late 90's early 2000's). But I know of 3 "backyard" bathysphere's that went "missing" on their maiden voyage (I was told you could buy the plan in the back of Popular Mechanics) that are verified as to people going out to test a bathysphere.
The world of private submersibles is wild, and has been since the 30's, who knows how many people have been lost along with their "labor of love", because they don't tell anyone. Like their wife or co-worker calls the police 2 days later and they find the boat just drifting. And I think that is the disconnect, it's not well publicized outside of specific fields (fluid dynamics is one of these fields, so at least when I was working on my grad degree, I heard all kinds of crazy stories from "Old Salts" that ended up teaching).
There seems to be at least some other design using it, but that they are being more thoroughly tested. Carbon Fiber Is Safe for Submersibles When Properly Applied (designews.com) I'd say it's a...
Exemplary
There seems to be at least some other design using it, but that they are being more thoroughly tested.
But with appropriate construction, that’s not a problem, [Composite Energy Technologies] asserts. To prove it, Hogoboom points to the record of his company’s products in deep-sea applications. “We’ve built vessels that we’ve cycled 200 times (to deep-sea pressures) and then brought to implosion and those fail at the same depth as new ones.”
The key is diligence in designing and testing the composite structures, Hogoboom explained. “We have a very high confidence in the strength of what’s been built,” he said. “We use engineering models, but we test to failure to validate what’s been modeled. That’s a crucial step that OceanGate has skipped," according to Hogoboom. “They never brought an exact clone to failure.”
I'd say it's a fairly long article, for modern standards, but it provides context and comments from others who have practical experience on work with the same type of thing. I mostly skimmed it for now due to time constraints, but intend to have a proper read soon.
EDIT:
Having now read the article (and taking it as truth for the comments below), they have quotes from Chase Hogoboom, president of Composite Energy Technologies, a Rhode Island based company "specializing in carbon fiber pressure vessels" which they have sold to both commercial and governmental customers.
Hogoboom agrees that there are legitimate concerns about using carbon fiber composite materials for submersibles. However, and just as the video points out, with proper testing it is possible to determine what is and isn't safe. With their testing practices, they've been able to build carbon-fiber composite unmanned underwater vehicles (UUVs), tested them both in laboratory conditions and in situ, and have examples of UUVs with over 6000 operational hours at over 6000 meters depth.
Note the key part that these are unmanned, which is extremely reasonable given the risk of loss of life if something goes wrong.
Part of this testing has included testing stress cycles, and then also testing to implosion, to check how the fatigue has affected their hull (although from context this appears to be specifically for laboratory tests, which is understandable but probably worth pointing out).
Some key quotes:
Carbon fiber is better in tension than in compression, Hogoboom concedes, but with appropriate design and manufacturing, it is an effective material for both, he said. “It is a more efficient material in tension, but it works very well in compression when used correctly.”
“We’ve built carbon [unmanned underwater vehicles (UUVs)] that are nearly 30 feet long with a large diameter that we’ve tested many times in lab facilities with all the equipment running. There’re ways to do this in a controlled environment.”
The company also has real-world results to back up those tests. “There are also examples of carbon UUVs with over 6,000 operational hours at over 6,000 meters,” said Hogoboom. “That’s in the real-world environment after many cycles.” As a result, CET delivers carbon fiber submersibles that reliably work at deep depths. “I feel very comfortable with what we do but it has taken a lot of testing to build up that confidence,” he said.
“We’ve built vessels that we’ve cycled 200 times (to deep-sea pressures) and then brought to implosion and those fail at the same depth as new ones.”
Taken as-is, this provides a strong contrast between what is good engineering practice on the side of Composite Energy Technologies, and the way OceanGate handled the development and testing of their submersible.
Not that a YouTube channel is a good source of research, but the hydraulic press channel recently tried to fatigue carbon fiber under pressure and found it didn't affect the crush depth. Granted...
Not that a YouTube channel is a good source of research, but the hydraulic press channel recently tried to fatigue carbon fiber under pressure and found it didn't affect the crush depth. Granted they used far fewer cycles and their submersible sucked, but an external experiment did recreate similar results.
I love the hydraulic press channel, but I would really really not rely on them for accurate testing information. :P Whereas Brian McManus, who runs Real Engineering, and made the submitted video,...
I love the hydraulic press channel, but I would really really not rely on them for accurate testing information. :P
Whereas Brian McManus, who runs Real Engineering, and made the submitted video, has a Masters in Aeronautical Engineering, wrote his thesis on "Deformation and Failure of Composite Materials" (which he talked about in the video), and actually worked as a Composite Design/R&D Engineer for several years before becoming a YouTuber. So I suspect he might actually know a thing or two about this particular subject. ;)
I completely agree that the hydraulic press channel is in no way scientific. Just wanted to add that their flawed testing still ended up with similar results.
I completely agree that the hydraulic press channel is in no way scientific. Just wanted to add that their flawed testing still ended up with similar results.
Searched for this too and could only find one example, another experimental (military) sub built by Oak Ridge National Laboratory for US Navy. Given the nature of this particular sub, it isn't...
Anti-regulation rich guy avoids regulation, dies to what regulation would prevent, kills 4. Genuinely no idea what makes it weird. In my mind, "freak accident" would imply a highly unlikely string...
Anti-regulation rich guy avoids regulation, dies to what regulation would prevent, kills 4. Genuinely no idea what makes it weird. In my mind, "freak accident" would imply a highly unlikely string of unrelated failures leading to an unforeseen tragedy. This was foreseeable and foreseen. The negligence was freakishly high, so there's that.
I’m not so sure it will be. I think it’ll just be another minor footnote, if mentioned at all, in the grand scheme of the story of the Titanic. The rest of the story of the ship is so fascinating...
I’m not so sure it will be. I think it’ll just be another minor footnote, if mentioned at all, in the grand scheme of the story of the Titanic.
The rest of the story of the ship is so fascinating and full of all sorts of crazy stuff already that I think once this fades into memory in a few years, it’ll be overshadowed by so many other things about the Titanic’s story/history.
Has it been confirmed that the composite hull failed and not the front window? the reason I ask is because in one of the wreckage recovery pics, a lift strap goes thru the window hole in the...
Has it been confirmed that the composite hull failed and not the front window? the reason I ask is because in one of the wreckage recovery pics, a lift strap goes thru the window hole in the titanium dome. Was the window removed to make recovery possible?
Have any pieces of the composite hull been recovered? If the hull failed by buckling, would there be some fairly large pieces? If the failure was with the window, would the composite hull fragment into many smaller pieces vs hull failure?
Seems like the side panels (fairings) were recovered largely intact.
The thing makes me wonder is that Stockton Rush graduated with an aerospace degree from Princeton - so smart guy and he should have know about the pros and cons of composites vs metals. Too bad he didn't appreciate the flip in design parameters of inward pressurized vs outward pressurized.
I agree there are still many unknowns - but I side with the rapid failure - the reason a sphere is the best geometry for a submarine pressure hull is because all the inward pointing force vectors...
I agree there are still many unknowns - but I side with the rapid failure - the reason a sphere is the best geometry for a submarine pressure hull is because all the inward pointing force vectors cancel each other out. A cylinder is pretty good but as soon as you get a slight amount of "out of round" the force vectors get out of balance and as you said a cascade failure happens. In other words the more it gets out of round, the weaker it is.
We'll have to wait and see if we ever get any of the official communication transcripts between the sub and mother ship. There's an unconfirmed transcript going around now that the sub crew heard...
I'm betting it will never be fully known what the exact failure point was.
We'll have to wait and see if we ever get any of the official communication transcripts between the sub and mother ship. There's an unconfirmed transcript going around now that the sub crew heard cracking sounds and the hull alarms were going off before they tried to ascend and ultimately lost contact.
There were some commentaries saying that the salvage crew might have remove the panel to lift the whole thing up. The salvage crew would have detail the parts removed. And the reason why they...
There were some commentaries saying that the salvage crew might have remove the panel to lift the whole thing up.
The salvage crew would have detail the parts removed.
And the reason why they believe that is because if that part failed, the window port would be in a worse shape than what is seen.
I'm going to guess that the window could have been blown out even if the hull itself failed. The energy involved is insane, Scott Manley computed something like 10kg of TNT per cubic meter of...
I'm going to guess that the window could have been blown out even if the hull itself failed. The energy involved is insane, Scott Manley computed something like 10kg of TNT per cubic meter of pressure vessel. Easy to imagine an instantaneous release of that to make a mess of anything nearby.
Hard to say for certain, since all the info I can find about recovered parts was from a few weeks ago, and it was all basically just speculation based on a few leaked photos of the recovered parts...
Hard to say for certain, since all the info I can find about recovered parts was from a few weeks ago, and it was all basically just speculation based on a few leaked photos of the recovered parts being offloaded onto shore. E.g. https://www.cbsnews.com/news/titan-sub-titanic-photos-implosion-debris/
A few other articles have mentioned them recovering parts with human remains in them though, so that would suggest at least some of the hull has been recovered.
But I don't think we will know anything definitive until the investigation concludes.
I thought they had been essentially vaporized by the pressure. On a more morbid note, I wonder what kind of remains those were, minced meat or actual body parts? Not a nice sight for sure.
A few other articles have mentioned them recovering parts with human remains in them though
I thought they had been essentially vaporized by the pressure. On a more morbid note, I wonder what kind of remains those were, minced meat or actual body parts? Not a nice sight for sure.
Youtube again, but this channel goes through: what happens to human bodies at that depth why submersibles are needed history of liquid breathing the Byford Dolphin accident, another explosive...
They only made a full dive to planned depth like 20% of the time... Red flag #1. Can only be opened from the outside, Red flag #2. They couldn't even buy a few Japanese legless chairs, You just...
They only made a full dive to planned depth like 20% of the time... Red flag #1.
Can only be opened from the outside, Red flag #2.
They couldn't even buy a few Japanese legless chairs, You just sit on the floor, Red flag #3.
I'm just going to say this here, but we are going to have a detail-by-detail breakdown of this event for the rest of our lives, aren't we?
Yeah probably. It's part of the Titanic's legacy now. It's also a weird story. It's an absolute freak accident and we had our hopes built up for a week only for them to have been for naught.
Having watched the video recently, I think one of the main points is that it isn't really a freak accident in the sense of it being unlikely to happen.
The video presents at least that they
(The above is from memory, so may be slight discrepancies - I do recommend watching the video as it goes through this in more detail than I can, including showing documentation such as articles and press statements.)
It may have been a freak accident in the sense that
but I think with the information as presented in the video it is a disservice to the engineering profession, best practices, and regulatory bodies that deal with safety to call this a freak accident.
EDIT: Just to add, this is not to say that with the information as presented this is definitely the underlying cause for the accident. Still, even if it isn't, it means the submersible was likely a tragedy waiting to happen.
Let's not forget the viewport, which was just straight up rated for a maximum depth of WAY less than their planned depth.
You make some pretty good points there. What should I call it if not a freak accident?
To quote Hot Fuzz, accident implies that no one's to blame.
A freak accident is completely unexpected. If a meteorite crashes into New York today and kills one person who happened to be standing on a manhole cover three blocks from the impact - that's a freak accident.
If you take a highly experimental submarine underwater after refusing to test it to modern safety standards and end up killing everyone on board, that's negligent homicide... But since you were on board, negligent suicide as well.
I think that tragedy is probably the word to use. A completely preventable and unnecessary tragedy.
An inevitability, given how many red flags and warnings the guy ignored.
With some consideration, I would in daily parlance probably go for tragedy instead of accident. To me, that has less connotations on the likelihood, predictability, or culpability of the event
I think I would use disaster in a more engineering-focused discussion, but in layman's terms, to me, it carries a bit too much sense of magnitude to be well-suited. Mind, I'm not a native English speaker, so my intuition here may definitely be off.
I would argue similarly about catastrophe, to me it feels too grand in scope to be applicable.
It seems pretty obvious that the correct characterization of this event is "entirely predictable and predicted result of criminal negligence." The only remarkable thing about it is that the perpetrator and a handful of of his cohort actually suffered the consequences of it - the much more common scenario is that a bunch of innocents suffer and the perpetrators get at most a slap on the wrist.
The whole situation also provides an interesting look into the mind of a wealthy businessman fully seduced by and absorbed into capitalist thinking. He so thoroughly had to convince others - including the rest of his company and other wealthy businesspeople - of his merits in engineering, innovation, and entrepreneurship that he believed his own myth and utterly sabotaged his perspective. I think that it spells out the relevance of the old adage of never assigning blame to malice when stupidity will suffice, in a world where the inherent malice of greed is already lurking behind every decision.
I like "catastrophic failure". It doesn't imply whether it was avoidable or not, and the failure was on the part of both the materials and the company's strategy of cutting corners and ignoring warnings.
It's an avoidable tragedy.
There were plenty of warning signs, but Stockton Rush ignored them and felt he knew better.
A unique accident.
It's the first submersible that we know of that imploded.
A quick google search shows that submarines have imploded before (and actually there’s quite a list of incidents since 2000 which I was surprised by). I think what made this such big news is that it was a private tourist trip. To my knowledge it’s a first in that sense, although I didn’t delve into the topic too deeply
Do you have a source? A quick search doesn't show any submersibles that imploded and no submarines where implosion was the cause of failure, just fires and explosions or leaks that made them sink below crushing depths.
They are pulling from the wikipedia, which is pretty easy to find. There were a lot of implosions in the 20th century, but the big one I know was the Thresher, which imploded during a deep diving test . . . in the North West Atlantic. But there were dozens, if not hundreds of subs that the primary cause of destruction was implosion during WWII and WWI, and that doesn't even get into the many many bathysphere implosions in the 60's and 70's (not an engineer, but a fluid dynamics guy . . . I find this shit fascinating), mainly from people building them in their backyards (you could buy the plans in Popular Mechanics) and then . . . just disappearing .
I would say in human history, a majority of the deep sea diving has resulted in implosions (watching footage from a ROV implode is something else, but it was meant to implode and had data loggers everywhere).
It's historical stuff generally (since geocities went down) not online. The Thresher is pretty well known though, it was the first US atomic sub that imploded do a depth test, but a lot of subs have "gone missing" (like the soviets lost somewhere between 2 and 15 subs . . . no one knows, and everyone that did know is dead).
Like, it's fuzzy math, we don't know that all these subs imploded, but . . . just take a look of the last 100 years, there are a lot of subs and submersibles "missing", not counting all the "off the books" subs (like narco subs) built in peoples backyards that . . . they just went out one weekend and never came back . . . like did they implode or did something else happen, we don't know but implosion is generally considered a leading cause.
I hear this stuff because I have a degree in a "related field" and made some friends when I was doing research at Scripps Oceanagraphy who I still talk to and keep up with the rumor mill. And a lot of it is the rumor mill, but if someone gets a ping on a hydrophone of an implosion happening at >300 feet (actually listening for whales) and then there is a search for a guy who went out in an "experimental" craft 2 days later . . . you can draw some conclusions . . . but if it's just some dude no one really makes a huge deal (like how many missing boats have you heard about this year . . . like in the last 10 years there has been a couple of hundred boats of normal people that just . . . go away, and most of us hear nothing about them).
https://www.npr.org/2023/07/05/1185979631/submersible-implosion-may-have-been-avoided-if-navy-design-principles-were-follo#:~:text=STEVE%20WALSH%2C%20BYLINE%3A%20In%20April,Bryant%2C%20a%20retired%20submarine%20captain (I can’t get the link to format properly) This came up on my first search, I haven’t had the time to look into it properly but from the brief search I did it appears there were a few incidents early on in military submarines (not just implosions) and they put necessary steps in place to reduce the likelihood of it happening again. However if anyone more knowledgeable has better information then please correct me
Malpractice-induced incident would seem a fair description.
An overabundance of hubris.
Negligence
That one will probably be argued about in court. An ex-employee sued them because they refused to do this allegedly impossible verification and subsequently installed an audio monitoring system to listen for cracks. This is not only totally inappropriate for the type of failure carbon composites experience, but also on a previous dive someone reported hearing cracks and asked for this to be checked out. For some reason this didn't happen.
Source: Video above
This about sums it up. It's not just a weird story, it's really quite extraordinary. As far as I'm aware this is the first time a submersible has actually imploded like this, not to mention inventor of the submarine was on board, not to mention they are literally part of the grave of the freaking Titanic. This story is absolutely insane and although incredibly sad, also morbidly fascinating. We'll be hearing about this for years to come, and for good reason imo.
I've heard this said before, but reading it this time, for some reason, makes me envision a movie/story of ghosts "living" on the titanic wreck. Alone for 70+ years on the ocean floor, then they start seeing submersibles, and now there are 5 new ghosts from the future.
There were "probably" a few dozen bathysphere implosions in the 60's and 70's that we just don't know about (this is based on urban folklore at Scripps in the late 90's early 2000's). But I know of 3 "backyard" bathysphere's that went "missing" on their maiden voyage (I was told you could buy the plan in the back of Popular Mechanics) that are verified as to people going out to test a bathysphere.
The world of private submersibles is wild, and has been since the 30's, who knows how many people have been lost along with their "labor of love", because they don't tell anyone. Like their wife or co-worker calls the police 2 days later and they find the boat just drifting. And I think that is the disconnect, it's not well publicized outside of specific fields (fluid dynamics is one of these fields, so at least when I was working on my grad degree, I heard all kinds of crazy stories from "Old Salts" that ended up teaching).
Are there any other deep diving composite fiber subs?
There seems to be at least some other design using it, but that they are being more thoroughly tested.
Carbon Fiber Is Safe for Submersibles When Properly Applied (designews.com)
I'd say it's a fairly long article, for modern standards, but it provides context and comments from others who have practical experience on work with the same type of thing. I mostly skimmed it for now due to time constraints, but intend to have a proper read soon.
EDIT:
Having now read the article (and taking it as truth for the comments below), they have quotes from Chase Hogoboom, president of Composite Energy Technologies, a Rhode Island based company "specializing in carbon fiber pressure vessels" which they have sold to both commercial and governmental customers.
Hogoboom agrees that there are legitimate concerns about using carbon fiber composite materials for submersibles. However, and just as the video points out, with proper testing it is possible to determine what is and isn't safe. With their testing practices, they've been able to build carbon-fiber composite unmanned underwater vehicles (UUVs), tested them both in laboratory conditions and in situ, and have examples of UUVs with over 6000 operational hours at over 6000 meters depth.
Note the key part that these are unmanned, which is extremely reasonable given the risk of loss of life if something goes wrong.
Part of this testing has included testing stress cycles, and then also testing to implosion, to check how the fatigue has affected their hull (although from context this appears to be specifically for laboratory tests, which is understandable but probably worth pointing out).
Some key quotes:
Taken as-is, this provides a strong contrast between what is good engineering practice on the side of Composite Energy Technologies, and the way OceanGate handled the development and testing of their submersible.
Not that a YouTube channel is a good source of research, but the hydraulic press channel recently tried to fatigue carbon fiber under pressure and found it didn't affect the crush depth. Granted they used far fewer cycles and their submersible sucked, but an external experiment did recreate similar results.
I love the hydraulic press channel, but I would really really not rely on them for accurate testing information. :P
Whereas Brian McManus, who runs Real Engineering, and made the submitted video, has a Masters in Aeronautical Engineering, wrote his thesis on "Deformation and Failure of Composite Materials" (which he talked about in the video), and actually worked as a Composite Design/R&D Engineer for several years before becoming a YouTuber. So I suspect he might actually know a thing or two about this particular subject. ;)
I completely agree that the hydraulic press channel is in no way scientific. Just wanted to add that their flawed testing still ended up with similar results.
Searched for this too and could only find one example, another experimental (military) sub built by Oak Ridge National Laboratory for US Navy.
Given the nature of this particular sub, it isn't surprising there's little information about it.
Thanks!
Anti-regulation rich guy avoids regulation, dies to what regulation would prevent, kills 4. Genuinely no idea what makes it weird. In my mind, "freak accident" would imply a highly unlikely string of unrelated failures leading to an unforeseen tragedy. This was foreseeable and foreseen. The negligence was freakishly high, so there's that.
I’m not so sure it will be. I think it’ll just be another minor footnote, if mentioned at all, in the grand scheme of the story of the Titanic.
The rest of the story of the ship is so fascinating and full of all sorts of crazy stuff already that I think once this fades into memory in a few years, it’ll be overshadowed by so many other things about the Titanic’s story/history.
Has it been confirmed that the composite hull failed and not the front window? the reason I ask is because in one of the wreckage recovery pics, a lift strap goes thru the window hole in the titanium dome. Was the window removed to make recovery possible?
Have any pieces of the composite hull been recovered? If the hull failed by buckling, would there be some fairly large pieces? If the failure was with the window, would the composite hull fragment into many smaller pieces vs hull failure?
Seems like the side panels (fairings) were recovered largely intact.
The thing makes me wonder is that Stockton Rush graduated with an aerospace degree from Princeton - so smart guy and he should have know about the pros and cons of composites vs metals. Too bad he didn't appreciate the flip in design parameters of inward pressurized vs outward pressurized.
I agree there are still many unknowns - but I side with the rapid failure - the reason a sphere is the best geometry for a submarine pressure hull is because all the inward pointing force vectors cancel each other out. A cylinder is pretty good but as soon as you get a slight amount of "out of round" the force vectors get out of balance and as you said a cascade failure happens. In other words the more it gets out of round, the weaker it is.
We'll have to wait and see if we ever get any of the official communication transcripts between the sub and mother ship. There's an unconfirmed transcript going around now that the sub crew heard cracking sounds and the hull alarms were going off before they tried to ascend and ultimately lost contact.
There were some commentaries saying that the salvage crew might have remove the panel to lift the whole thing up.
The salvage crew would have detail the parts removed.
And the reason why they believe that is because if that part failed, the window port would be in a worse shape than what is seen.
I'm going to guess that the window could have been blown out even if the hull itself failed. The energy involved is insane, Scott Manley computed something like 10kg of TNT per cubic meter of pressure vessel. Easy to imagine an instantaneous release of that to make a mess of anything nearby.
Have any pieces of the composite pressure hull been recovered?
Hard to say for certain, since all the info I can find about recovered parts was from a few weeks ago, and it was all basically just speculation based on a few leaked photos of the recovered parts being offloaded onto shore. E.g. https://www.cbsnews.com/news/titan-sub-titanic-photos-implosion-debris/
A few other articles have mentioned them recovering parts with human remains in them though, so that would suggest at least some of the hull has been recovered.
But I don't think we will know anything definitive until the investigation concludes.
I thought they had been essentially vaporized by the pressure. On a more morbid note, I wonder what kind of remains those were, minced meat or actual body parts? Not a nice sight for sure.
Youtube again, but this channel goes through:
They only made a full dive to planned depth like 20% of the time... Red flag #1.
Can only be opened from the outside, Red flag #2.
They couldn't even buy a few Japanese legless chairs, You just sit on the floor, Red flag #3.