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u say the people on the titan didn't know that it was going to implode and didn't feel anything. i think that's short sighted. they obviously knew it was going to implode for some time because of the early warning system, unless you're saying that was broken
An 18 minute video about an event that happened in a few milliseconds, plus an ad for something I will never buy. I'm glad I can skip through the video
@@hnrwagner not really. It's pretty clear to most people why you don't build a submarine the way they did. We don't need to simulate triangular wheels made of porcelain. Same kind of situation.
@@AlexRojas-db6yd hey maybe you have time to waste. And money for the sim tools licenses. The rest of us have to work for a living, so no, nobody but jobless hackers "simulate everything".
@@TheNefastor You seem irrationally upset about this which leads me to conclude it triggered you due to some tangentially related but otherwise indirect reason. It's OK man, I'm mad about poor allocation of resources too.
As a retired submariner, sub test eng [nuc] /test director [HM&E], etc, you've presented the best vid yet, from engineering perspective and justifications, thru the simulations. As we said in the old days [and who know, perhaps even now, "OUTSTANDING SIR" Thanks.
Almost like something happened to make it fail the moment it did. Now what story was breaking when every news channel in the world cut to this story for 2 weeks? It won't be coincidence.
It's not 'amazing'. It shows their calculations were valid. We barely had any safety factor when we made it to the moon. We got lucky there wasn't an accident. If we had lost an apollo 13, these voices would have damned the whole program.
@@mstecker The calculations were valid for the first dive only. otherwise Titan ran on concentrated luck. Unlike metal which can safely flex without loosing strength. Fibers break as the hull is slightly distorted under extreme pressure. The breaks accumulate and can not be repaired. The Titan Hull RTM system used microphones to listen and count these noises to anticipate failure - they knew. Stockton Rush cut every corner he could to keep oceangate going. why?
IMO this is not the problem. The problem is how can someone with the intelligence of a monkey just go ahead and do this? Why no agency holding him back? Is it his charisma? People just don't care?
@@KidCorporate I think he tried to save money (this carbon winding can be much cheaper then titanium hulls(they basically build a smaller spherical titanium hull and increased its internal volume massively by the carbon tube)) But the cost savings only accounts for manufacturing and not development where it seams like they cut costs (quoting wrong safety factors shows that they did not know there design/validate their calculations)
Why can’t the producers find an actor who knows the subtleties of the English language to read the script? This AI voiceover is irritating and distracting.
Listening to Stockton Rush's interview sniplets is like watching one of those notorious YT videos of pakistani repair jobs where - at the undertone that material sciences are but a joke for westerners - completely destroyed machinery parts are nursed back to 30-50% of structural grade and put back to work - only to break just in time for the next miracle repair video take.
The Titan was towed for 3 days 600 miles across the ocean on teeter-toter tin pontoons. It's structural integrity was shaken to pieces on the stormy Atlantic. On top of that any sensible maintenance/servicing was not possible on a tender leash.
The Titan was flimsy in terms of deep see operations but not as flimsy as you describe. Yes maybe internal panels were most likely shock loose but those were held in place by magnets iirc. Sea wave induced amplitudes couldn't have done much, if any to it's integrity.
@@hnrwagner each titanium cap was attached to a steel structure, while rather heavy carbon tube was suspended in air, the left/right pontoons were effectively twisting each end cap in random directions, this torsional effect was not ideal for the glue bonding joints at each end of carbon tube; must understand, those thin aluminum pontoons were designed for a lake not for 5m Atlantic waves;
I am at 0:06 and there you have it. At the depth of the Titanic, even seawater is compressed some. People say, or think, that water is incompressible, but it actually gets a little bit more dense the deeper you go. Even titanium compresses a tiny, tiny amount under the pressure at Titanic depths. The carbon fiber composite compresses, more than seawater, more than titanium. The glue joint between the carbon and the titanium was never designed to move or flex with these different rates of compression. Plus the view port design and construction were never meant for that depth. In the images of the recovered debris being unloaded in port, the viewport was separated from the titanium hemisphere.
I have found a diploma thesis "Adhesive Joining of Metal End-caps to Composite Pressure Vessels ", I will study it and present the results, maybe you find your thoughts back in it
@@hnrwagner They cleaned the bonding surface with a dirty rag, and you can see the technician touch the surface with his bare hands after wiping with the dirty rag. This was clearly shown in an Oceangate video.
@@hnrwagner They mixed the glue by hand, and probably used additives to thicken it, and I doubt it was properly mixed in. They also stirred in lots of air, and never degassed the glue. Bubbles in the joint material would be bad news as well.
@@rtqii That was the first PV. The second one was done by electroimpact, which is a quite reputable company that does a lot of aerospace composite work. They ended up abandoning the first PV and hired electroimpact to make a new PV.
@@rtqii I feel you're right about the trapped contaminants and especially the air bubbles, the CFC shell basically got 'the bends' in more ways than one. Delamination from air being compressed out of the layers, it's presence reducing the overall bonding and the compression expulsion decreasing the mass. In an interview with Karl Stanley, who was onboard for a test dive, he remarked that the noise of fireworks from the CFC was almost constant, not only on the way down to 2000 metres, but all the way back up until 300 metres. To me this would indicate the compression of the CFC's mass itself while descending, likely with lateral folding of individual fibres, then on ascenscion the 'wrinkled'/weakened fibres are snapping apart as the CFC shell expands again. Even though the ends of the cylinder only suffered one quarter of the total compression, I feel these lateral forces were woefully underestimated. Karl strongly recommended they should cancel all plans for passengers until they built something else far more robust. He wasn't on the team, he'd built deep sea tour subs and they wanted his input and he was very keen to ride, however oceangate sacked several of their own engineers who also recommended scrapping the design and ignored any cautions from the international submersible society.
Based on the fact that they had dropped their ballast before the implosion, I am guessing that everybody knew what was coming, there would’ve been a large amount of cracking and creaking so much so that it scared them enough to drop the emergency weight, which had never been done before at that depth.
There are two great tragedies the emerged from the implosion of the Titan. First and foremost, the loss of the passengers. And second, the fact that Stockton Rush never found out that his hubris caused the death of four people.
Rush's talk about how they were monitoring this hull for microscopic cracking noises and that this would make it all ok was chilling. Personally, I'd want to hear or see NO cracking and creaking coming from the hull.
Rush was misapplying technologies from the aviation industry meant to predict component failure over time. The type of system employed is effective in measuring vibrations using accelerometers and computer analysis on key components such as drive shafts, engines, bearings, generators, et cetera. Problem is these technologies require someone to know what the failure mode truly looks like and it is clear it was never tested enough to figure out any baseline. I believe it was more a marketing measure to "promote" a culture of safety where no enhancement of safety actually existed. To a person without knowledge of how these things work his BS would have persuaded many.
@@jahnkaplank8626 This was not a 'plastic' tube. You are correct in refusing to go based on the information available. You probably lack the perspective of a billionaire. There are safer ways to do this type of research. There is a fair argument that carbon fiber hulls can be useful in comparable applications. However, much research and testing is needed, something Ocean Gate deliberately avoided. Ocean Gate hurt the industry they were supposedly supporting in their actions.
That's why carbon fiber was NEVER considered safe to use in deep water environments. That's why people wrote letters to the oceanic communities that govern accreditation to WARN of the dangers that Oceangate chose to ignore. It's nothing short of murder what Stockton Rush and Ocean gate did.
@@hnrwagner English is a bitch. Same spelling, different pronunciation, entirely different meaning. So you got the word right, the narration picked the wrong version (I'm assuming it's text to speech)
I've been looking forward to seeing your simulation ever since seeing it referenced in jefostroff's "Best Titan Sub Implosion Simulation video" a week ago. Thank you for posting your video, it was well worth the wait!
Timecodes: Chapter 1 - Introduction: 0:00 Chapter 2 - What is CFRP: 1:05 CFRP vs. Titanium: 2:58 Chapter 3 - Design of Oceangates CFRP cylinder: 4:34 Manufacturing of the CFPR cylinder: 4:39 Analytical Design of the CFRP cylinder: 6:35 Numerical Design of the CFRP cylinder: 7:47 Interview with Stockton Rush on Safety Margin: 10:26 What a proper testing program look like: 12:50 CFRP cylinder with safety factor of 6: 14:21 Chapter 4 - Implosion: 14:32 Cycle Fatigue explained: 14:38 Debris of the TITAN: 14:51 Implosion vs Human body: 15:11 Best TITAN Implosion Simulation: 16:41 How a safe cylindrical submersible looks like: 17:48 Google Scholar: scholar.google.de/citations?user=a4sKEKsAAAAJ&hl=en Researchgate: www.researchgate.net/profile/Ronald-Wagner OrcID: orcid.org/my-orcid?orcid=0000-0003-2749-1455 GitHub: github.com/hnrwagner ABAQUS like FREE to use FEA Software: prepomax.fs.um.si/
I'd just like to let known my severe objection to the use of David Attenborough's voice for the AI narration generated for this video. It's inappropriate, unnecessary and the great man himself would surely object.
Yes what is that all about? It's not a light topic, is it? So why add this humorous touch to it? Why not narrate the video yourself? Computer voices give a cheap or even disingenuous impression anyway. We all make mistakes, so even if you yourself think little of your performance as narrator, it's probably still way better than this.
Still remember sitting here at my desk when the news broke of this. The wife was talking to me. I said, yup they're all dead. Turned into pink paste before they knew it was happening. There is a reason more people have been to the moon than to the deepest part of the ocean. It's easier.
Cabon fiber pressure vessels are very good at resisting internal overpressure since the loading can be engineered to produce almost purely stretching forces on the fibers. Using it to resist external overpressure is an astonishingly bad idea. In the composite formation process control has to be extreme, and the inspection of the material would have to be high tech, meticulous, and frequent. Just the delusional attitude to safety is something the responsible parties should be prosecuted for.
In the early 90s I worked at David Taylor Research Center with engineers that were designing, testing and building composite submarine hulls. They knew what they were doing. I worked in other applications in composite materials and did my Masters Thesis on composites. We had a saying: "You can't push on a rope" The composite sub hulls they designed were for much shallower use that what the idiot Rush was trying to do.
One might investigate the timeline of his bypassing safety testing v.s. his decision to avoid needed certifications by declaring every passenger to be a "mission specialist" and part of the "crew". If it can be shown that he came up with that idea of making all passengers crew to avoid the need for certifications, then I'd say that should qualify his company for murder charges.
@@pete540Z That's another point: if he had used this submersible more reasonably, and kept to shallower depths, it might have gone on being useful for many many years.
@@hnrwagner He really should have gone with it, the fact it would have added extra 20+ ton to overall vessel, mostly in larger thrust motors and batteries and the floatation chambers would make it way bigger, requiring a much larger launch vessel, is why he baulked at the design. Promises had been made and he was impatient to get paying passengers. I really think he should have just gone 100% Titanium and had the dang thing on a cable, used a deployable anchored floating rig or similar. Could still be manouverable but with much lighter thrusters and batteries with the option for emergency cable power. But he had his heart set on a mini sub like he saw on thunderbirds.
I was pleased to see that you did make reference to the potential for material property data variability associated with such analyses. There have been a number of these failure simulations since the Titan loss. I have not seen any detailed presentation against material property data used … the simulations seem to be generally created more for dramatic impact than a genuine study of the specific case. There are 2 major factors that appear (to me) to be consistently ignored: 1 - The challenges associated with creating monolithic laminates of 100mm thickness or greater (the effort required to develop an appropriate manufacture/cure cycle to control the innate exothermic process and the consequences of failing to understand the resultant effect on “assumed” material property data. How was degassing of such a tremendous monolithic laminate controlled through the cure cycle? 2 - The challenges associated with developing an appropriate adhesive bond; both in terms of the CFRP/Ti connection and in terms of the way the load will transfer across that interface as the CFRP cylinder will deform compared to the Ti end rings. A lack of basic understanding and qualification appears to manifest in the (admittedly limited) visual evidence in the apparently clean surfaces of the Ti rings when they were recovered … no apparent evidence of residual adhesive or trace of laminate indicating the failure as being adhesive rather than cohesive. Such failure is not surprising to me given the on-line video evidence of the adhesive application and assembly of the Ti rings to the CFRP. What primer/pre-treatment was performed to both the Ti and the CFRP? How was adhesive thickness and uniformity controlled? How was the adhesive cure process developed and controlled with due consideration to the thermal properties of both materials? So many questions. There has been much maligning of the use of CFRP in this application .. and I am not saying it was the optimal choice .. but if a typical aerospace development process had been applied, it might have become a proven alternative to a traditional solution. However, it would have required a very protracted learning curve and very extensive test programme (small scale coupon tests through to varying degrees of test samples) before ever thinking of bolting a human inside and subjecting them to such slim safety margins and I have not identified any indication of such effort being undertaken. Perhaps, one day, an appropriate solution employing advanced materials will make the ocean depths more accessible … but not without an appropriately cautious development process.
I have built like 10 years ago a 65 mm thick CFRP plate and thought it was very thick, the curing cycle was every 10 mm and it had a pretty good quality. From an old oceagate video I saw that they cured like every inch (25.4mm). I am not a fan of such thick composite structures. I have found a diploma thesis regarding the CFRP-TI interface and will present the results in the coming days, I am not an adhesive specialist though.
@@riaganbogenspanner According to Karl Stanley who went on a test dive in it, it made a noise like fireworks all the way down and up again, only ceasing above 300 M.
These calculations overestimate the strenght of the submarine in my opinion: I do not think that the standard composite failure models and strength calculations can be applied to a submarine as hydrostatic pressure leads to carbon fibers becoming thinner, but longer, the epoxy reacts homogeniously by just reducing its volume, with a much lower overall volume modulus that is. This leads to additional stresses at the fiber matrix interface and different failure modes - you would expect the overall resistance of the vessel to be much lower than predicted with current failure models. In addition: If the panels had even minor leaks water would have entered the cracks forming in the composite (because composite) which would have moved the point where the water pressure acts on the structure into the composite in the affected areas leading to stresses directly delaminating the composite and promoting buckling which would have removed structural integrity.
@@hnrwagner i have did some assumptions. i could not find any sources about the internal volume, so i approximated it with a 2.5m long cylinder with 1.5m radius. so the initial volume is 4.42 m^3. i also assumed 1 atm inside before implosion then, for the initial temperature, i am not sure. there was 5 average sized people there, so they were heating up the air with ~500w in total, but the water around them is very cold, but to my knowledge carbon fibre is bad heat conductor. so i just went with a 25c initial temperature. the final pressure is 400atm. the issue is that i cant really write equations here very well, so i just write the final one. essentially i used the Boyle's law and ideal gas law. the final equation is T2 = T1 * (P2 / P1)^((γ - 1) / γ), where y is 1.4 (y is the adiabatic index, 1.4 for air) this is assuming that no heat is excanged during the implosion. so T2= 298.15*400^0.286, so around 1600K while there are assumptions and simplifications, i think it is at least somewhat correct, but i can be wrong
Either way it was all over in 6 milliseconds, so sudden their nervous system ceased to function before it could register anything. It's no surprise they were unable to find bodies nor cylinder, would have been atomised.
Please edit the soundtrack to remove the sibilance sound (Ssss) by tapering off above 5,000Hz. You may then want to add reverb using a preset, perhaps one named 'small room.' In future recordings, use a sibilance filter (made for the mic or use pantyhose stretched around a bent coat hanger).
CFRP also _fatigues_ more in than Titanium. So the Titan did fine for about 50 dives, as they ignored all the stress on the hull. Then the last time-- CRUSH.
From a former student in engineering materials, I salute you. Best video in RU-vid regarding the Titan's demise. Clear, concise and to the point. Thank you for your service.
This video starte.d with a plea for money from a well known children's hospital on my phone...I gave to the charity...my info was promptly sold elsewhere...I received over 60 different beggers in the mail several times each..it has taken me months to slow it down and my time and money...I now only donate to one or two and only anonamously...watch out...😢
No one held accountable for this incident with a failing structure to a vessel. Is more mind boggling, than it could have ever discovered on the ocean floor.
Disclaimer : not an engineer or material science expert. From what I can see, using CFRP was not automatically a bad idea for a submersible. Where Oceangate - and specifically Stockton Rush- went wrong was mostly about not doing adequate safety checks. Why wasn't the sub properly tested before it went in the water. They had no idea about failure depth or the number of times the sub could successfully go to 4000m and return before failure was virtually guaranteed. Why wasn't proper testing done on the hull after each excursion? (Well i think we can all guess), and why does it seem that the only test that was done was on a scale model? And that test failed but they still took the thing out. Stockton Rush believed he was operating without a map. And so he was, but the role of the pioneer is to create the map, not willfully continue on blindly. If he truly believed in CFRP as a groundbreaking material for building submersibles then he's done enormous harm to the possibility of it become standard practice. By not even attempting to back up his claims with real data, he's likely caused reduced funding for other research into the use of CFRP as investors will be reluctant to throw money at it after a disaster of this type. If there is a way to use it safely he's probably slowed advancements in this area of study for a generation.
Not sure if the voice is AI or an inexperienced voice artist. Either way, it's not great. The whistling and mistakes are very distracting. Use your own voice, you do an excellent job!
Wouldn't be surprised if the crew had a slight notice of what was going to happen. My guess is it started making loud noises and buckling sounds before the instantaneous implosion.
Oh ..I think they knew they were in deep doo doo...sounds...trying to drop ballast ..the thing was more n likely on end with them all piled on top each other on one end and absolutely nobody able to do anything anyway...
@@hnrwagner I enjoyed it, good mix of dry nerd data and cheeky satire. Probably the first video I've ever watched where the AI voice wasn't repellent or used decietfully. I dare say even David Attabro would approve.
13:20 No one building deep sea submersibles has done those kind of tests. But that might be because titanium and steel are considered known materials? The testing done on the spheres of Deep Sea Challenger and DSV Limiting Factor have been to put them under about 25% higher pressure than their maximum dive depth (and maximum ocean depth...). Pressure of 14 000 meters compared to max dive depth of 11 000 meters.
It's insane to think that the energy in this is five times the low end energy - and so within the range of a detonation of the W54 nuclear warhead (using in SADM demolition charges, or the Davy Crockett manpad.)
I think I'll start a new line of soft drinks called Stockton Crush....Each can will have a picture of a smiling Stockton with his quote underneath "You are remembered by the rules you break"....Available in eight implosively exhilarating flavors:...Blueberry Burst, Lemon Hubris, Arrogant Grape, Narcissistic Lime, Orange Psychopathy, Chocolate Idiocy, Titanic Cranberry and our absolute favorite: Strawberry Slime..........Available for only 250 000 a case.............Feel the Rush.....Feel the Crush..........Stockton Crush: Bet you can't drink more then one!.............
@@hnrwagner They sacked and sued the engineer that told them much, much, much more testing was needed on the Titan prototype before selling tickets, forcing him to sign an NDA.
@@hnrwagner 2017 shell was analyzed with COMSOL/M by Spencer Composites who also fabricated it. 2020 shell was analyzed by Collier Aerospace with their HyperX software, fabrication by others. Given their customer base, I doubt HyperX is optimized for thick walled vessels at 60MPa external pressure.
A slightly DIFFERENT implosion theory: That simulation makes sense if the carbon fiber tube failed and the end caps essentially smashed together with tremendous force thereby compressing and heating everything in between them. However, we know the window wasn’t rated for the pressure it experienced so what would the simulation look like if the window failing was the start of the implosion? In that case, logically it seems like the window would be traveling inward at a high velocity being pushed by an extremely powerful jet of water thereby causing a different implosion sequence. One reason I thought that might’ve happened was because the end caps that were recovered appeared to be undamaged at there flanges where they mated with the carbon fiber cylinder. If the cylinder had failed and the end caps were forced together with tremendous force and speed then you’d think they possibly would’ve contracted each other with sufficient force to cause noticeable damage to the end cap flanges. Does anyone think the window implosion theory is plausible? Lastly , great video! I think it would be really interesting to see the implosion sequence slowed down even further. 👍
An implosion in this scenario is followed by an instant catastrophic explosion. Perhaps you can consider a diesel engine, although they generally have a glow plug now, earlier models did not as this only assists combustion, unlike a spark plug that initiates it in petrol/gas engines. So what actually ignites the diesel/air mix is the heat from the sudden compression of the air by the upward stroke of the piston. An implosion catalyzed explosion is the same physics, the 1 atmosphere air void that the high pressure water is rushing in to, to equalise the overall pressure; is instantly compressed to above that of the surrounding water and the temperature soars, then the explosively expanding super-heated air also turns the surrounding water to steam which also expands. Voila, an explosion equal to 1 ton of TNT, which would level a city block.
@@_andre99 that all makes sense. Watching the implosion simulation presented in the video and seeing how the two end caps came together in “4 milliseconds” was what got me wondering about having two seemingly undamaged end caps. That whole sub would be imploding at several hundred mph so you’d think the momentum of the end caps coming together would leave obvious signs of damage. Although, that implosion video was obviously only an approximation because if you watch it closely it shows parts of the cfrp cylinder proceeding through the bodies of the end caps which we know didn’t happen based on the recovered undamaged end caps. I guess we’ll never know exactly what happened but it’s definitely interesting to think about.
I think what happened is, you have two main components, a FLEXIBLE composite tube, with two titanium end caps. Think of a toilet paper tube with metal end caps. The pressure probably bowed the tube part along the axis like pushing your finger down on the middle of the toilet paper tube. It probably became great enough to flex the tube and break the bond of the glue attaching the end pieces causing catastrophic failure.
I think the piece his design team missed, was analyzing the low cycle fatigue limits through a properly modeled finite element simulation. Which would have required product testing to establish conservative material properties, based on the haul manufacturing.
it was supposed to have a positive buoyancy when it released its weights, so it could return easily to the surface, that's why it was built with a CFRP cylinder
Exactly like the expert says, further it is very difficult to provide things like working ballast tanks at the depth they wanted to go to. So if the sub isn't inherently buoyant it is a very hard problem to solve, particularly for something small that is supposed to maneuver.
Neutral buoyancy meant the submersible was lighter without a need for syntactic foam. This reduced construction costs and made operations cheaper. Sadly, CFRP compressive pressure vessels are an underdeveloped field and Oceangate didn't invest the time and money to properly build out their experience base.
@@josue_kay You could in theory build a negatively buoyant sub that relies on hydrodynamic lift or propulsion to control depth, but the failure mode of this is not ideal.
That old "woonded teeta neeumm" will get ya every time, I tell ya. Strange how Sir David cant seem to pronounce very common words in The Queens. Odd, that.
One thing that baffle is I just recently learn they had numerous issues with previous pressure vessels. Like many i was lead to believe they scored successes all the way up to the fatal implosion. They had issues with their earlier subs and this was Titan's second pressure vessel. I'm getting to the point where I think Rush knew far too well one of these trip would soon be his last.
Also the fact that the only thing that held the CFRP tube to the titanium domes was some random glue, applied by hand (!). Not quite sure that the many inside/outside diving cycles in cold and salt waters were a good thing for something so fragile as a polymer. Stockton Crush knew his white diving pill was never gonna last long...
Trying to bond a titanium ring with Pippi Longstocking super gluer to a titanium ring, in a dusty building is suicidal for a pressure vessel trying to hold against 6000 psi.
1:33 - CFRP is 3X lighter THAN Titanium. Proofreading is important. Understanding the definition of a word is more important. Or maybe just as important.
I've only read a few comments down, so forgive me if I repeat another's. As someone who has peer-reviewed papers on almost exclusively medical topics, one thing I "dinged' the author for, every time and without fail, was spelling errors. Someone should always proof-read a paper, essay, letter, anything that will be read by another, especially those whose job it is to identify not only errors of research and testing of a hypothesis, but also grammatical and spelling errors. How much do you "love your baby," as we call it, if you make mistakes that go uncorrected? So far, and I am literally at the 0.05 timestamp, I see that the word "acrylic" is spelled "aryclic." [sic] Since we live in a world where spell check has been ubiquitous for decades, it's simply inexcusable to present any work that another will see that contains errors of this nature. Even as I type this, my own machine's spell check wants to correct the intentional mistake I made by misspelling your own. Please, proofread your work before presenting it to SAMPE. I guarantee these types of errors will not go unnoticed, and though you may not be submitting for publication, and I somehow feel you are, it will still leave a bad taste in the mouth. I look forward to the rest of your video, as I am sure the science itself will be presentable, whether or not it is sound. Good luck to you. JDSMDPhD Addendum: At ca. 17:30, while demonstrating TNT equivalence in pressure gradients, did you mean to say "tons," or "metric (tonnes) or "tons?" As there is a difference. J
Thanks for the comment, I checked it for spelling errors and didn't find all of them. The video was sent for peer review 2 times. I hope you enjoyed it nevertheless.
There's an additional factor that received very little attention at the time. CFRP and titanium are both slightly compressible especially at 38 or so MPa. But they compress at different rates. IIUC, titanium is a little more compressible than CFRP. Thus, the adhesive joint between the titanium end-ring and the CFRP cylinder would be under considerable tension at the design depth.
Quasi iso layup? ~[0/90/90/90] no 45s at all. You're strength calcs are way low. I agree it was low cycle fatigue. They had strain gauges all over the inside of the hull to augment their acoustic sensors. That data if ever released would be very interesting
I hate to be that guy but I guess you didn't have permission from David Attenborough to 'use' his voice ? I would have appreciated the video more without this -possibly- ethical issue.
You need to teach your AI the difference between the verb "wound" - to injure a living plant or animal, and the verb "wound" - the past tense (among other tenses) of the verb to wind.
If only the Titan was designed as a 5 dives maximum life limited sub with full replacement of the carbon fiber component, Rush could have pulled this off as a viable commercial operation.
The videos of Oceangate manufacturing showing the guys not wearing masks, suits or hairnets, while building the hull explains it all. Those people have no idea how serious it is to ensure there are no impurities.
So basically, you're going down 2½ miles to the ocean floor under unbelievable pressure that can turn your body into a DNA smoothie, in a hardened ball of yarn. Where do I sign up?
