Did I miss it, or has no-one posted anything about the Titanic submersible catastrophic failure, as it would appear to be an engineering failure of the highest order.
It's ironic that the hubris of the Ocean Gate CEO, who poo-pooed safety concerns, and fired one person who questioned the safety of the design, apparently led to his death in his own creation.
Karma's a bitch.

 

Its been talked about.
https://forum.allaboutcircuits.com/threads/glad-im-not-a-passenger.105696/post-1829864

 

I don't pay much attention to current events but this one is an exception. As a submariner this one is of particular interest to me. The Titan submersible is an example of inexcusable stupidity. Every new detail that comes out is another facepalm. It's inconceivable how someone so successful could be such an idiot. It's almost as if he wanted to go out with a globally televised bang and take a few others with him.

 

I don't pay much attention to current events but this one is an exception. As a submariner this one is of particular interest to me. The Titan submersible is an example of inexcusable stupidity. Every new detail that comes out is another facepalm. It's inconceivable how someone so successful could be such an idiot. It's almost as if he wanted to go out with a globally televised bang and take a few others with him.

Money talks and usually doesn't listen.

 

My guess is that he was a true believer in his technology. Afterall, he believed in it enough to use it himself repeatedly.

It's not uncommon for "innovators" to be true believers and convince themselves that all of the skeptics simply don't understand THEIR technology, There IS a lot of hubris involved, but the same can be said for many of the people that brought forth innovations that have had drastic impacts on the world.

I don't have a huge problem with people risking their own lives in experimental craft, which this most definitely was -- and, to be fair, they went to great lengths to point out to their customers that it was an experimental craft. Where I think that a closer look needs to be taken are the conditions under which lay parties, most particularly paying customers, can be allowed to ride in experimental craft.

All of that aside, the lack of unmanned testing (as least as it is currently being portrayed) reflects very poor engineering practice. Unlike space craft where the launch costs are so enormous that you have to really limit the number of unmanned test flights, this would seem to have been a case where performing dozens, if not a hundred, dives using a prototype craft would have been relatively inexpensive. A normal manned dive took eight hours. Even if you did the test dives that way, you could take the ship out for a week and get in twenty dives. But you could (and should) make many of those dives and ascents as fast as possible, probably double the number of dives. You get to a hundred dives doing that, and you can make a pretty defensible claim that the technology and design is reasonable safe. The next thing you do is take your unmanned prototype to really deep water and take it down until it fails. The claim is that all of these sensors would detect a problem in plenty of time to surface the vessel. So demonstrate that. You get two birds with one test -- you get to demonstrate it's actual crush depth and you get to demonstrate that your safety systems actually work.

 

My guess is that he was a true believer in his technology. Afterall, he believed in it enough to use it himself repeatedly.

It's not uncommon for "innovators" to be true believers and convince themselves that all of the skeptics simply don't understand THEIR technology,

Yeah he was plainly a true believer, and if he thought skeptics didn't understand his technology then he was right, because nobody understood it, least of all him. There is very little design data available for carbon fiber compressive pressure vessels and none for carbon fiber tubes with titanium breasts epoxied onto the ends.

There IS a lot of hubris involved, but the same can be said for many of the people that brought forth innovations that have had drastic impacts on the world.

This is true, and I suppose for every Orville or Wilbur Wright there has to be a handful of Stockton Rushes. The difference between them in retrospect can be simplified to whether or not they failed spectacularly. But if I was going to risk my life for something it would have to be something truly novel. Like "first man to step foot on Mars." What he risked his (and others) life(s) for was more like "457,869th man to step foot on Mars, but the first one to do it in a rubberized polyester unitard instead of a space suit."

I don't have a huge problem with people risking their own lives in experimental craft, which this most definitely was

Agreed.

to be fair, they went to great lengths to point out to their customers that it was an experimental craft.

Agreed

Where I think that a closer look needs to be taken are the conditions under which lay parties, most particularly paying customers, can be allowed to ride in experimental craft.

Yeah, I went on a flight in an ultralight aircraft (hang glider with a propeller-driven tricycle under it) and had to sign a waiver stating (I think, it's been years) something to the effect of it being an experimental aircraft and some such. But people are flying these things all over the world and I saw it as a formality. I had reason to believe I would not die. These passengers absolutely did not. Did they know that? Who can say?

When you say "Where I think that a closer look needs to be taken..." I absolutely agree, but who will be taking this closer look? AFAIK this waiver was signed in international waters and the ship they were on may as well have flown the flag of Djibouti (I don't know what flag it flew, point is ships fly flags of the least restrictive country they can). I think the best we can hope for is that this will be a wakeup call and wealthy would-be passengers signing up for things like this in future will do their own due diligence and find out just how experimental an experiment thing is before they make themselves part of the experiment.

All of that aside, the lack of unmanned testing (as least as it is currently being portrayed) reflects very poor engineering practice. Unlike space craft where the launch costs are so enormous that you have to really limit the number of unmanned test flights, this would seem to have been a case where performing dozens, if not a hundred, dives using a prototype craft would have been relatively inexpensive. A normal manned dive took eight hours. Even if you did the test dives that way, you could take the ship out for a week and get in twenty dives. But you could (and should) make many of those dives and ascents as fast as possible, probably double the number of dives. You get to a hundred dives doing that, and you can make a pretty defensible claim that the technology and design is reasonable safe. The next thing you do is take your unmanned prototype to really deep water and take it down until it fails. The claim is that all of these sensors would detect a problem in plenty of time to surface the vessel. So demonstrate that. You get two birds with one test -- you get to demonstrate it's actual crush depth and you get to demonstrate that your safety systems actually work.

Excellent suggestions, and I hope I can say this without detracting: all relatively obvious ones, and only a small sample of the relevant excellent suggestions available to give. I don't doubt that these suggestions (among many others I that know of) were given not only by unaffected parties on the internet after-the-fact, but also leading up to the tragedy, by experts in the field, and were ignored. This was a miscarriage of engineering, logic, and every kind of sense. They left not a single corner uncut. Really terrible. I don't have the words to express how egregious the negligence was at every step of this death march.

 

When you say "Where I think that a closer look needs to be taken..." I absolutely agree, but who will be taking this closer look? AFAIK this waiver was signed in international waters and the ship they were on may as well have flown the flag of Djibouti (I don't know what flag it flew, point is ships fly flags of the least restrictive country they can). I think the best we can hope for is that this will be a wakeup call and wealthy would-be passengers signing up for things like this in future will do their own due diligence and find out just how experimental an experiment thing is before they make themselves part of the experiment.

The ship still has to set sail from a port (which in this case was Canadian) and the port authority has some options as far as not letting the ship dock and/or not letting it set sail. How effective actions like that might be and/or how easy they would be to circumvent is certainly an issue.

At the end of the day, there's a limit to how much you can do to prevent people from going stupid on themselves, including not exercising due diligence before undertaking something as a passenger in a high-risk endeavor. There is also the risk of going overboard. If I build an aircraft in my garage, it is going to be classified as an experimental aircraft. Does that mean that I shouldn't be allowed to ever take up anyone with me? I would think that that's going too far. But would having some kind of a reasonable inspection and certification process be required before I can carry passengers be going to far? That's much more up in the air, with reasonable arguments on both sides. What about before I can carry paying-passengers? I think that might already be the case, but I'm not sure. If not, I think that a much stronger argument can be made that regulations like that are reasonable.

 

From a different perspective:

Does wealth somehow justify encumbering the rest of us with the duty of cleaning up your mess?

Examples are:

Boat owners whose incompetence at sailing or navigation require the Coast Guard to expend time, effort, and money to rescue them from their own flawed choices?

"Explorers" whose incompetence at planning, equipping themselves, or navigating require expensive and resource hungry rescue operations?

The list can go on. We could and should require financial responsibility from these people such that the rest of us don't suffer at all on account of their choices. Purchasing insurance to cover such things, refusal of public agencies to engage in rescue operations for such cases.

For example, the Coast Guard eventually limited their response to stranded pleasure craft to cases of direct threat to life, and will not assist the vessel only the people. "Call Sea Tow" was a common refrain on Maritime Channel 16 when a mayday turned out to be nothing more than a bad captain running aground while the charts clearly showed soundings much too shallow for the vessel.

Perhaps make it a crime to embark on a dangerous "adventure" without insurance to deal with the possible failures of it. If you are rescued you are both financially and criminally responsible.

This is kind of a sore spot for me. I think it is an immoral act to make society pay for failed recreation.

 

There is very little design data available for carbon fiber compressive pressure vessels and none for carbon fiber tubes with titanium breasts epoxied onto the ends.

Anyone know if carbon fibre composites suffer in a similar way that metals do from 'work hardening' and 'metal fatigue'?
I'm thinking that even if Titan survived several dives to 3400 metres, there might have been some build up of stresses and micro-fractures which ultimately led to the implosion.

 

Anyone know if carbon fibre composites suffer in a similar way that metals do from 'work hardening' and 'metal fatigue'?
I'm thinking that even if Titan survived several dives to 3400 metres, there might have been some build up of stresses and micro-fractures which ultimately led to the implosion.

Thirty years ago, whilst working for Lloyd Instruments (now part of Ametek) we marketed an acoustic test device which listened for the "pings" of micro cracks in composites under stress - used for non-destructive and destructive testing skis, crash helmets etc. Carbon fibres are intrinsically brittle so they are held together by epoxy resin. Theoretically very strong but the problem in practice is the process of laying down the layers without any air gaps or other inclusions which would cause discontinuity weakness where cracks would start and expand. Hopefully the whole hull was rigoroursly tested with ultrasonics but I've not heard any mention of it. Also, any discontinuity in the structure, like the hatch or the window where different materials meet would introduce much higher local stresses - an airliner could be half the weight if passengers didn't have windows, and given the need to reduce fuel consumption I predict this may happen soon.

Presumably there will be evidence of finite element analysis of the whole structure although from what we have learned so far I begin to doubt it. I was astonished that their was no mention of an externally attached tethered radio beacon which would rise to the surface, automatically triggered to release.

If it was the UK I would argue there was criminal negligence here.

 

Also, any discontinuity in the structure, like the hatch or the window where different materials meet would introduce much higher local stresses

I assume any wiring going through the hull to an external acoustic transducer for the comms would similarly cause local stress concentrations.

 

Anyone know if carbon fibre composites suffer in a similar way that metals do from 'work hardening' and 'metal fatigue'?
I'm thinking that even if Titan survived several dives to 3400 metres, there might have been some build up of stresses and micro-fractures which ultimately led to the implosion.

Yes this is exactly right and this is a critical part of the design data we have on the metals used for pressure hulls, that we don't have for carbon fiber. Nobody on earth (except now Stockton Rush, who is dead) can tell you how many dives to what depth will cause a 5" thick carbon fiber hull to weaken to failure.

Theoretically very strong but the problem in practice is the process of laying down the layers without any air gaps or other inclusions which would cause discontinuity weakness where cracks would start and expand.

Yes and this makes me question whether it is actually possible to ever develop data on carbon fiber as a pressure hull material. The data we have on various grades of steel, titanium, aluminum, that we have relied on for many decades of submarine hull design all assume homogeneous materials. I don't think it's possible to make a carbon fiber hull homogeneous. In addition to the inclusions you mention, as the size of the hull grows it becomes harder and harder to get it to cure uniformly. If a hull takes hours or days to make and hours or days to cure, then by the the time you're maybe only 10% done laying layers, the first layer has already cured. I think this will result in something like "tree rings" with different layers cured to different degrees of hardness depending on the temperature of exothermic reaction and other factors. Then there is variability in the resins used, the fiber used, etc. It seems far too many variables to ever be predictable enough to stake lives on.

Hopefully the whole hull was rigoroursly tested with ultrasonics but I've not heard any mention of it. Also, any discontinuity in the structure, like the hatch or the window where different materials meet would introduce much higher local stresses

They had ultrasonics permanently installed on/in (if I understand correctly, embedded in) the hull to monitor for cracks in real time but one of the pieces of expert advice that they willfully ignored was that this system would only give them a few mS of advance warning, if even that.

If it was the UK I would argue there was criminal negligence here.

There absolutely was criminal negligence no matter what country you look at it from. The guy who needed hanged for it already hung himself, not sure if anyone else in the company will be held liable. I think the only person involved who can't have a finger pointed at them is the guy they fired for trying to call a safety stop and who blew the whistle on them and was subsequently legally browbeaten into silence.

 

They had ultrasonics permanently installed on/in (if I understand correctly, embedded in) the hull to monitor for cracks in real time but one of the pieces of expert advice that they willfully ignored was that this system would only give them a few mS of advance warning, if even that.

Makes you wonder if it was worth installing in the first place. The mere fact of installation would have introduced inhomogeneity and hence a potential problem source.

 

In response to this statement.

" I think it is an immoral act to make society pay for failed recreation. "

Well, some wealthy people pay more taxes in a week than some of us pay in a lifetime.

So, the idea that someone must pay for an insurance policy to go hiking up a mountain or some such will probably result in creating an environment where only wealthy people can afford "recreation".

If it is found that there was criminal neglect, then that company should be held responsible for the resources used for the rescue mission.

 

In response to this statement.

" I think it is an immoral act to make society pay for failed recreation. "

Well, some wealthy people pay more taxes in a week than some of us pay in a lifetime.

So, the idea that someone must pay for an insurance policy to go hiking up a mountain or some such will probably result in creating an environment where only wealthy people can afford "recreation".

If it is found that there was criminal neglect, then that company should be held responsible for the resources used for the rescue mission.

But we don’t use their money to scale up operational capability of search and rescue, and the theory of taxation doesn’t include the idea that if you pay more you are entitled to more from the public purse.

“Ordinary” recreational activities don’t run the risk of requiring hundreds of thousands of dollars in otherwise unfunded rescue operations, and while the might include the possibility of a normal emergency medical response, we do generally expect that the person needing the help bears financial responsibility.

It is the case that the wealthier a person the more able they are to create a situation which will require heroic efforts to rescue them from very costly situations that serve no purpose other than personal satisfaction.

Perhaps look at it this way, when they decide to do something exceptionally risky and spend the money to do it, they are not budgeting for the failure of that thing and instead relying on the fact that we. collectively, do value human life enough to spend so much on preserving their’s. even if the danger is entirely of their own making and includes negligence.

Even if the money is eventually forthcoming, there isn’t extra capacity in our emergency services waiting for them, and so they put others at risk unilaterally when their endeavor fails for predictable reasons.

To put a fine point on it, if you can’t afford to “go hiking up a mountain” unless you do it ill-prepared and ill-equipped you are doing just what the people I am talking about are doing: encumbering society for purely personal benefit if you do it.

On the other hand, if you are prepared, and well trained and equipped, you could buy insurance for a reasonable cost since insurance companies will build risk pools based on actuarial realities and offer policies whose cost is scaled to the level you would be encumbering society if you’d not purchased it.

 

This video is an interesting source of information:

 

This video is from a completely different, and very interesting angle:

 

This video is an interesting source of information:

The links in the description of that video are worth looking at if this topic is of interest.

 

“Ordinary” recreational activities don’t run the risk of requiring hundreds of thousands of dollars in otherwise unfunded rescue operations, and while the might include the possibility of a normal emergency medical response, we do generally expect that the person needing the help bears financial responsibility.

It is the case that the wealthier a person the more able they are to create a situation which will require heroic efforts to rescue them from very costly situations that serve no purpose other than personal satisfaction.

Quite the contrary, ordinary recreational activities, including hiking, skiing, boating, rafting, flying, and the list goes on and on, routinely result in major search and rescue efforts and reimbursement is almost never sought. I was a search and rescue member for many years, primarily for missing/downed aircraft, but we were called out for all kinds of search, rescue, and recovery missions. While cries for demanding that the victims be billed for the cost of SAR efforts went up anytime a claim was made that they should have known better, the only time I can recall that any actual effort to bill on any mission I was involved with was when a guy intentionally went missing in order to make some point to his family. I think even that was dropped because there was no evidence that he intended to cause a search to be initiated and wasn't aware that one had been undertaken until he showed back up.

Another thing to consider: Does society benefit from having international airline travel available? Well, if an airliner goes down, who is responsible for conducting search and rescue operations? The country of origin? The company operating the plane? Local officials? Who is responsible for paying for those operations? This was a significant barrier to the development of international air travel and how it was resolved was by international treaties that state that, unless that country specifically designates someone else, the air force of the country over which an aircraft, any aircraft, flies is responsible for any SAR efforts required and are expected to bear the cost. Apparently the consensus was that societies benefit sufficiently more from such activities than the costs involved. In the United States, the US Air Force (via public law) has delegated those responsibilities to the Civil Air Patrol and the Air Force acts primarily in a coordination and support role. In large part, this is because the Air Force doesn't maintain the right kind of aircraft and other equipment for these duties (CAP has a fleet of about 550 aircraft, mostly Cessna 182s which are very well suited to the task in most locations, plus can call upon a very large number of member-owned aircraft when needed), let alone have them in sufficient quantity and spread out sufficiently wide to provide the kind of rapid response that is needed. But they also recognize that CAP, being an all-volunteer organization, can perform these missions at a much lower cost.

On the other hand, if you are prepared, and well trained and equipped, you could buy insurance for a reasonable cost since insurance companies will build risk pools based on actuarial realities and offer policies whose cost is scaled to the level you would be encumbering society if you’d not purchased it.

I'm a bit skeptical about that. Consider general aviation. Almost all insurance policies, including accidental death and injury policies, explicitly exclude flying in any aircraft unless it is as a passenger on a regularly scheduled route (the details of the exclusion vary quite a bit, but that's a common one). Fly in a private plane and get killed? Almost certain that your insurance won't pay out. Charter a private jet? Same thing. Having said that, you can purchase life insurance that doesn't include the exclusion, but it is at a significantly higher cost (or at least it was when I was actively flying, haven't checked in the last couple decades), far out of proportion to the increased risk.

 

Quite the contrary, ordinary recreational activities, including hiking, skiing, boating, rafting, flying, and the list goes on and on, routinely result in major search and rescue efforts and reimbursement is almost never sought.

These are good points and I understand the rationale, but I do disagree they refute my position. The fact that there is a dilemma concerning recovering the cost of rescue is a problem to be overcome, not (for me) evidence that it shouldn’t happen.

And, think you for your participation in S&R. Volunteer organizations, including S&R groups, are a very good example of people at their best. My volunteer work focused on disaster response, but the spirit is very much the same.

I think, though, that volunteer S&R speciality organizations are generally being funded by the community that most benefits from them, or by charitable donations where the contributions are voluntary. Adding public funding to help ensure these organizations are viable, when that is done, doesn’t bother me because the isn’t a matter of purity and lives are precious.

A really amazing example of such organizations are the UK charity air ambulance services. Volunteer staffed and lead, and charity funded with the absolute latest SoTA kit and techniques and demonstrably saving lives (though frequently from the victim’s own hubris or negligence).

I personally donated to the Scottish Charity Air Ambulance who have a very clever funding scheme whereby if you donate monthly you are participating in a lottery worth £1000.00. You might win that, but if you don’t you are still supporting an organization worth funding, directly and unambiguously.

Not being eligible for the lottery (no UK bank account) I just gave directly. But the main point here is that community funded organizations are distinct from “public” ones in that they are voluntary, and additional capacity not the baseline.

Concerning air travel, that’s a vexed question. While it would certainly be true that S&R focusing on international flights would disproportionally benefit the wealthy who will be more likely to take such flights in their lives, our general standard of living might be seen as tied to people who take such flights to support industry and innovation. It’s very hard to pick apart such a complex relationship.

Concerning GA, it is famously a domain of the well off, and also famously suffers from disaster-by-incompetence. Why chutes are not mandatory on GA aircraft since they certainly seem to stop deaths, I don’t know. Nonetheless, from what I have seen and read, GA misadventures are overwhelmingly the result of pilot hubris, incompetence, or both. It’s hard to understand how public resources can reasonably be committed to mitigating the risks of such completely voluntary activity accessible. in general, only to the well off among us.

So, insurance for GA maybe well reflect the actuarial reality for the insurance companies. I don’t know, but an activity which depends on literally not falling out of the sky, and one where falling out of the sky is surprisingly common (as opposed to the amazingly robust person-mile record of commercial aviation) does seem like one that would be expensive to underwrite.