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A similarly 'perfect' safety record was held by the original De Havilland 'Comet' airliner, until they began to disintegrate in flight with metal fatigue.

Which is my point. Idea > Design > Construction > Use > Failure > Investigation > Reassessment. It's pretty easy to look back upon any failure afterwards and suggest that something should have been done differently.

This submersible is the first of its kind to go that deep, and did so several times successfully. An investigation should determine how it failed, and then that type of construction will be reassessed for future designs.

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Why use this developing technology when weight isn't the critical issue?

There are indeed reasons:

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Metallic hulls, however, because they are not buoyant in designs for depths of more than 2,000m, present challenges when it comes to managing ballast for ascent and descent. In particular, metal-hulled craft require the use of syntactic foam attached to the outside of the craft to achieve neutral buoyancy...... the company had been evaluating the potential of using a carbon fiber composite hull since 2010, primarily because it permits creation of a pressure vessel that is naturally buoyant and, therefore, would enable OceanGate to forgo the use — and the significant expense — of syntactic foam on its exterior

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I’m pretty sure contrary to what a1bjcd thinks, it is zero.

See, that's the deal. I don't think about what an answer should be. If I'm posed with a question I don't know the answer to, I try to seek it out so that I can provide an accurate answer.

For example:

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nd I also think this thing made three (3) dives to depth at most. I guess technically 2 dives since the third one didn’t work out.

Your thoughts are incorrect, and the answers are not that terribly difficult to find:

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By the end of 2021, the team had accomplished 10 successful dives to the Titanic: four at depth along the debris field and six surveys of the wreck. Titan’s large viewport allowed three people to simultaneously view and document the Titanic as the pilot and copilot attended to the controls.

And that's just to Titanic at the end of 2021. It doesn't include the many other dives to other sites and test dives made prior to this incident, nor does it include additional dives to Titanic after 2021.

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Originally posted by DennisM:

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Originally posted by heathtx:
On Everest, there is extreme levels of training required to make the attempt.

I disagree. These days, you need intermediate training, and crap-tons of cash to make an attempt. Buckets of money will get you to base camp (either Tibet or Nepal side) whether you're actually prepared or not, because many of the guides in that space are mercenary and unethical.

From there, you'll have a plethora of photo opportunities before either a) having to turn back to avoid dying, b) just dying, or c) for a minority of groups attempting to summit, actually spending a minute or two at the roof of the world before hopefully descending alive. Published "success rates" are usually around 2/3 for climbers who attempt to summit, but generally don't define upfront what constitutes an "attempt" (spoiler: it's not just setting out from EBC.) But the idea that it require superhuman, extreme training doesn't jibe in any event with published studies that show a) climbers on Everest are on the whole LESS experienced than 30 years ago, but b) more of them are making it.

The key? Money. Pools of money for technology and human assistance. Kind of like diving on the Titanic?

100% correct.

I used to do high altitude mountaineering, and have done other peaks in the Himalayas. I've been to Everest base camp, and have friends who've been on top of Everest and numerous other big peaks.

With about the same training as someone generally in good shape would put into their first marathon, I've gotten to about 20,000 feet without supplemental oxygen. I lifted weights 3x per week and trail ran with ankle weights most mornings for about 6 months.

Many who go up Everest these days are nearly hauled to the top by their Sherpas. Porters carry all their equipment. They have plenty of O2 bottles pre-staged for them. The route is set and roped by Sherpas, making it more of a hike than a climb. The environment is hazardous, and there is a very real physiological risk from hypoxia, but it is not anything like hollywood makes out mountaineering to be.

I think that they saw something down there and could not be allowed to share it. The whole carbon fiber argument is a rouse to keep people from questioning the reason rich folk would pay that much to risk their lives to look at a crusty old hulk. There had to be some other reason they wanted to go down there, aliens, mermaids, some other crazy shit who knows? Who cares?

In the time the media has been pouring it’s attention on the deaths of these 5 assholes who basically committed suicide by stupid how many pedestrians have been killed by autos? How many important things have been ignored so the world can discuss the details of a sub constructed by a douche bag? I for one will not rest until the mermaid angle has been fully investigated!

quote:

Originally posted by Stlhead:
I think that they saw something down there and could not be allowed to share it. The whole carbon fiber argument is a rouse to keep people from questioning the reason rich folk would pay that much to risk their lives to look at a crusty old hulk. There had to be some other reason they wanted to go down there, aliens, mermaids, some other crazy shit who knows? Who cares?

Pardon me?

Explain this remark, please.

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I think that they saw something down there and could not be allowed to share it.

The leftist hatred for the wealthy and the deaths of these people is sickening.

I'm just waiting for Stlhead to tell me about the underwater UFOs.

Really, stuff like that- it's something you would never want to post in this forum, so I'm looking for an explanation as to why I see totally whacko conspiracy theory shit in this thread. Unacceptable

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This submersible is the first of its kind to go that deep, and did so several times successfully. An investigation should determine how it failed, and then that type of construction will be reassessed for future designs.

This type of construction has already been evaluated and used where appropriate. It works great in aircraft and other similar uses, within it's design limitations.
If it had been properly tested, as responsible parties pointed out both before and after, it wouldn't have come close to passing. It only went through a small number of cycles, however many dives it did, as a test. A real certification would have been a number well over the expected pressures and cycled well over (multiple times) the number of cycles expected in service. Then it would have been limited to some number based on those tests. Maybe even not certified at all if the results were as poor as this one sample would indicate.
The information now looks like it failed somewhere between 3-4000 ft. depth, well below the Titanic's depth.
These guys weren't technological pioneers, they were kamikaze tourists or thrill-seekers. This wasn't a matter if it would fail, just when, and these guys were the crash test dummies.

My calendar says Sat not Sun…….
Might as well join in with a drink nonetheless.

If you wanna build yourself something that may kill you fine.
If you want to build something for monetary gain and inflate your ego, follow them set in stone rules that work.
Like on at least 7" of hull thickness, a 2 mile cable teather and such.

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This type of construction has already been evaluated and used where appropriate. It works great in aircraft and other similar uses, within it's design limitations.

Yet there are other companies that are using it for deep sea applications, even as pointed out by others in this thread. Seems that it does indeed have viable uses.

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If it had been properly tested, as responsible parties pointed out both before and after, it wouldn't have come close to passing. It only went through a small number of cycles, however many dives it did, as a test. A real certification would have been a number well over the expected pressures and cycled well over (multiple times) the number of cycles expected in service. Then it would have been limited to some number based on those tests.

Nobody is arguing that the owner of this submersible didn't cut corners and take unnecessary risks. But there sure seems to be a lot of people making statements of fact that simply aren't true.

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This wasn't a matter if it would fail, just when, and these guys were the crash test dummies.

Isn't that true for every single mechanical device that exists on our planet? Every single deep sea submersible will eventually fail if given the chance. That's how technology advances. Failures lead to success.

You're a big fan of this guy, I see.

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Isn't that true for every single mechanical device that exists on our planet? Every single deep sea submersible will eventually fail if given the chance. That's how technology advances. Failures lead to success.

That type of testing may have been OK in the days of Orville & Wilbur Wright but science has advanced a bit since then.
I made and flew paper airplanes as a kid but they didn't contribute to science and I didn't put anyone's life at risk based on my knowledge, especially third parties.

Real testing on something like this would have the known failure points documented, set operational limits, and then maybe advanced from there.
This has none of that, just guestimates based on theory. Just wishful thinking, and we see how that worked out.

https://www.independent.co.uk/...-flaws-b2363243.html

OceanGate Expeditions CEO Stockton Rush said he was “personally insulted” after an industry expert raised concerns about safety flaws in the Titan submersible, which imploded killing five crew members on Sunday.

Former OceanGate consultant Rob McCallum warned Rush that he was endangering passengers’ lives and urged him to stop using the vessel until it had been independently certified, emails reviewed by the BBC showed.

Rush dismissed Mr McCallum’s concerns as “baseless cries” and accused him of trying to stop innovation in the deep-water submersible industry, the BBC stated.

Mr McCallum, the founder of the deep-sea research and tour company EYOS Expeditions, consulted for OceanGate in 2009 before leaving in part over concerns that Rush was rushing development of the vessel.

In a 2018 email, he told Rush that he was “potentially placing yourself and your clients in a dangerous dynamic”.

“I implore you to take every care in your testing and sea trials and to be very, very conservative,” he wrote. “As much as I appreciate entrepreneurship and innovation, you are potentially putting an entire industry at risk.”

In an eerie warning, Mr McCallum added: “In your race to [the] Titanic you are mirroring that famous catch cry: ‘She is unsinkable’”.

Rush defended the company’s credentials and denied there were any safety issues with the Titan in a heated response a few days later, according to the BBC.

OceanGate’s approach to maritime engineering “flies in the face of the submersible orthodoxy, but that is the nature of innovation,” he wrote.

“ We have heard the baseless cries of 'you are going to kill someone' way too often .”

“I take this as a serious personal insult,” he added.

The tense exchange ended when OceanGate threatened legal action against Mr McCallum, he told the BBC.

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Originally posted by a1abdj:

Isn't that true for every single mechanical device that exists on our planet? Every single deep sea submersible will eventually fail if given the chance. That's how technology advances. Failures lead to success.

Not necessarily. Those who ignore (the Titan CEO, for example) lessons learned by others may discover that failures only lead to more failures. Who would go to his company now and say “Now that your designers know what doesn’t work, build me one that does”?

I don’t think the question is whether carbon fiber is useful, or can be safely used in a number of ways. The question is whether any of the other uses involve subjecting a carbon fiber cylinder that is attached to other materials (the titanium end bells) and subjected to multiple cycles of extreme external pressure.

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Real testing on something like this would have the known failure points documented, set operational limits, and then maybe advanced from there.

Can you give me some examples of what "real testing" is? I've read several articles that have discussed testing that has been performed on these carbon fiber vessels prior to and after construction.

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Those who ignore (the Titan CEO, for example) lessons learned by others may discover that failures only lead to more failures.

I'd say that those lessons won't be ignored going forward. Progress.

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You're a big fan of this guy, I see.

I'm clearly not a fan of this guy based on my comments in this thread. What I am a fan of is factually based discussion versus emotionally based opinions as far as the technology is concerned.

One question, could the failure of the under-rated viewport cause implosion? Trying to understand the physics involved.

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The information now looks like it failed somewhere between 3-4000 ft. depth, well below the Titanic's depth.

I was under the impression the Titanic lies on the ocean floor at around 12,500 ft. depth?

How do the pressures involve compare to those in CF nitrogen/air tanks?