NTSB Titan Sub Report: Carbon Fiber Hull Defects, More

[@jeffostroff]

🎥 WATCH NEXT: 🎥 Coast Guard Has OFFICIAL OceanGate Titan Sub Transcript: kzbin.info/www/bejne/r3_UoWWVbJWbrck 🎥 OceanGate Titan Sub Debris Video Shows How It Imploded: kzbin.info/www/bejne/mXe0eH2BqLNghsk 🎥 OceanGate Titan Sub Coast Guard Hearing SHOCKING Facts: kzbin.info/www/bejne/n2ippJiea5l_p5o 🎥Coast Guard Video: Titan Sub Salvaged Off Ocean Floor: kzbin.info/www/bejne/mImTZauDmtJmY6s 🎥 Link to Azget Industries KZbin Channel 3D Titan Video: Titan Submersible and how it Imploded... parts of submersible recovered 1600 feet from the Titanic kzbin.info/www/bejne/aH-VlHZ5msqhkM0si=vH4-17xnxwOE6iiv

[@IDNeon357]

There's definitely human remains. Human bodies are extremely strong. I worked as a FDNY 9/11. It was a myth that everyone was pulverized. No one was pulverized. We pulled them out for many months crammed into void spaces. Thousands.

[@shaunofthedead3000]

Cheap glue outgassed. Outgassing compromised layers. Thru layer sanding created escape points for outgassing and compromised glue over multiple compression/decompression events. As gas escaped it compressed and water intrusion began. 1st pop was an outer layer massive single delamination event. Either expansion or contraction of one layer over a large section of hull at a different speed that neighboring layers. The signal, control, and other technical issues were a result of sensors secured to the carbon fiber experiencing excessive movement. Eventually the delamination and cross layer sanding areas lined up so that the implosion from external pressures occurred. Initial infiltration spot would be around the front titanium ring on one side only. Subsequent dive retrieve cycles would further work to decouple the titanium and carbon fiber glue joints. This would push stuff both front and aft, but the decoupled front cone would very quickly relieve the pressure wave as it smacked everything to the back cracking the less compromised parts of the hull resulting in a fairly small footprint for the largest pieces of the remaining main hull.

[@AstroHolden]

@ 10:30 That doesn't look like a crack. It looks like a piece of twisted metal rail. You can also see what appear to be three rivet placements in the image along the length of the rail.

[@sferg9582]

Am I the only one here questioning the use of carbon fiber in compression? A cylinder made from carbon fiber in compression is no stronger than the resin holding it all together. Carbon fiber's strength is in tension, not compression. I think the designers were sniffing the carbon fiber and getting a high thinking it's THE stuff to use since it's supposed strength is the end-all-be-all solution to everything strong. In this case the wrong application. A chain gets its strength when in tension.....have you ever tried to PUSH a chain?

[@goody2shoes384]

Your videos are always so interesting

[@timkowles728]

I'm retired from 45yrs in aviation. While working at Textron Aviation, I was composite certified for carbon fiber and Kevlar repairs. When working carbon fiber, you never sand thru layers of fiber. If you do, you just compromised the structural strength of the carbon fiber. Just the fact they were sanding out wrinkles in the layers means that whole area was compromised. The peelply is woven teflon fabric used for keeping bagging material from sticking to the epoxy matrix during curing. after cure, the peel ply is just peeled off and discarded.

[@jeffostroff]

Thanks for that info Tim!

[@MarkShinnick]

How do you feel about the concept of using carbon hoops primarily loaded in compression?

[@robertfindley921]

If you buy a carbon fiber bicycle, all the salespeople will *profusely* warn you that if it is damaged in any way, (hint, like when you hear a "big bang") it is *not* safe and *not* repairable. And loud noises carry great energy which can cause damage elsewhere.

[@TheFrewah]

Thanks, I missed that.

[@cremebrulee4759]

Thanks for your expert input.

[@kellymcdonald9552]

Aerospace NDT Inspector here: this is horrifying on a whole other level. Delamination, porosity, cracks, I look for these things down to .030" and reject them due to the fact that they'll eventually grow to threaten the structural integrity of the vehicle. To think that something this riddled with defects was sent down nearly 2.5 miles underwater... absolute death trap. Thank you so much for the great analysis!

[@realulli]

3800 m isn't even close to 4 miles. More like 2.5 miles. Your point does stand though, carbon fibers have awesome tensile strength. That means, they can withstand enormous tension. Compression-wise, they're just threads. Imagine pulling on a rope, then pushing on it.

[@kellymcdonald9552]

@@realulli Didn't check the details before posting. 🤷‍♀️ Still, even a mile down would have been the same result eventually.

[@michaeloswal9847]

When you try to make gains by cutting safety, you won't make gains.

[@Beauloqs]

​@@kellymcdonald9552 typical youtube expert.

[@kellymcdonald9552]

@@Beauloqs Uh, yeah... you're on KZbin. Spoilers?

[@devzeppelin1911]

If Rush hadn't died in the implosion he'd be royally fucked right now.

[@mikestraley7201]

100% culpable

[@benjurqunov]

Would that be grounds to deny special homosexual rights ? He wasn't no illegal mexican !

[@Daledugahole]

If you build a submersible that implodes with people inside, you better be in it when it does

[@AceyCamui]

I think that's kind of want he wanted. When his 'investment' went south, he didn't want to be around to have any kind of accountability. He was an absolute cheap ass narcissist.

[@un_censoreship]

He's pretty royally fucked right now... 😵‍💫

[@thomasm.7058]

Thanks for all the details and the calm analysis... I am not an expert on submarines, but I was a welder in the German military for mobile bridges and anything that was sunk in water. All our work was checked with ultrasound. Sorry, I would never trust my life to any technology that I couldn't check down to the smallest detail.

[@jennyjones7370]

That's why you're still alive

[@thindigital]

Maybe the loud noise on dive 80 was the 5 inch thick hull becoming 5 one inch thick hulls when the layer adhesive failed in a hoop

[@nobiazcustomsinc5030]

my exsct thought

[@BDudasProductions]

My same thoughts too. Did bringing it through an ultrasonic testing would have detected it?

[@thedbcooperforum]

The loud bangs were going on with every dive...

[@sabagecabage7828]

@@thedbcooperforumyou did not finish the video...

[@thedbcooperforum]

@@sabagecabage7828 sure did

[@krags.allander2465]

This is the best video of the aftermath of the Titan I've seen. Very well done.

[@ryanrohauer5940]

the idea that they were sanding down inperfections is BONKERS to me thats obviously going to weaking the carbonfiber wraps... INSANE

[@ThatSockmonkey]

And the wraps were cylindrically laid out, so there was no cross reinforcement of the fibres, because the curing time to do it better wasn't fast enough for Ol' Fishfood Rush Edit Not that it would have helped that much. Carbon fibre is strong for its weight, and incredibly useful for many other applications, but you can't cheat physics, and compression strength is not a major component of the utility of carbon fibre.

[@KimoKimochii]

The fact that he sands CF tells you everything you need, he has 0 clue what CF physically is

[@dbz9393]

none of them were using gloves or sanitary gear when they were adding adhesive etc :')

[@KimoKimochii]

@@dbz9393 none of them were using their brain

[@groundhog-plays]

Company was ran by a megalomaniac.

[@s.porter8646]

Retired submariner, this thing was an accident waiting to happen..see thresher...many corners cut, and no inspection and recertification, I'm an so not surprised! One the company that built it, two, many submersible professionals advised not to construct like this

[@nick13b]

my god, you can see blood and goop in the videos

[@thindigital]

@@s.porter8646 the contrast between the testimony of experienced sub people and the OG engineers has been stark.

[@ellabella6099]

@@nick13b no it’s not, it’s likely the colour of the oxygen tank . They were very careful not to put out distressing photos they said for the victims and families involved but I thought like you at the time 🥺

[@ellabella6099]

@@s.porter8646 I’m not surprised either having listened every day to the inquest .

[@s.porter8646]

@@ellabella6099 rich people making poor decisions

[@ssbf1095]

I've watched more than a few videos on Oceangate, and yours is the best of all of them as far as explaining complicated topics to the general public. The graphics help a lot, too. Thank you!

[@manofaction1807]

Anyone who walks into an established close-knit community like divers and submariners, and throws money around like a drunken sailor just to try to come in and "Rewrite the rules", needs to be avoided and exposed at all costs. These people are guilty of negligent homicide. The arrogance, lack of safety, and lack of their own amature self awareness exhibited by all involved is just staggering. For all involved, Carbon Fiber is not used to make submersibles, no matter how much you wish it to be so. parts, maybe, depending on the part, but not for deep dive subs. This is just tragically comical at how willfully arrogant in their ignorance this whole organization was in this endeavor.

[@JK-tr2mt]

Hence all the disclaimers they had to sign! At $250,000 must be one of the most expensive funerals - for each of the so called "mission specialists!"

[@LatitudeSky]

The irony of throwing around money is that the company was desperately struggling to make money and basically lived paying customer to paying customer just to survive. So they HAD to dive to get paid to make money and dive again with the next sucker. This meant safety was less than secondary compared to the need to dive to survive. The ultimate plan for Oceangate was to have a fleet of these submersibles operating around the world so the company could just sit back and cash the checks. The vehicles were just a revenue source. But that meant they had no other real purpose. They had to make money.

[@stampedetrail2003]

The idea about leaving the mandrill in place or using a titanium cylinder instead of CF. What do you think of that?

[@jesusismful]

Problem is they didn't have enough money to throw around and ended up skimping contrary to the engineering requirements and recommendations by experts.

[@TorianTammas]

​@@stampedetrail2003a cylinder is much weaker then a sphere, but steel or titanium are the materials to use as they resist pressure from all sides.

[@flapjack413]

@10:25. That's not a crack. Note the five bolt ends protruding from it. I think it's the twisted remains of the steel frame that the outer skin attached to.

[@frederickmontes9094]

i agree, my first thought was it was the landing skid

[@wattage2007]

My immediate thought too.

[@abelis644]

Agreed.

[@colin-nekritz]

100% immediately recognized it was the steel frame from the bolts, yet another thing that frustrates me about Jeff, he brings good content clues others don’t but continually be it this or back to the Surfside (Champlain Towers) has not one f’ing clue what the hell he’s talking about.

[@kennethney4260]

Yeah, I commented the same thing before I saw your comment

[@jackieschulz2028]

What a great video and detailed description of all the photos. I had no idea this much of the submersible was recovered.

[@Mikahaan]

Jeff, those green things are the green oxygen bottles that were on-board to supply oxygen to the internal atmosphere ... they are totally crushed and folded from the energy of the implosion. Solid steel O2 bottles!

[@caseycat]

I came here to say the same thing

[@X1erra]

Solid steel? Crushed and folded? I heard it takes 45000 Psi to crush solid steel, or at least 42 tons per square inch of force...

[@stampedetrail2003]

Okay I was working under the assumption that this was Stockton's wet suit.

[@thornie123]

I know it’s morbid of me, but I was kind of hoping they were bloody blankets. I know I’m not the only one. We all want to see the bodies but there probably are none left.

[@Simoxs7]

@@X1erra 45000 PSI is about 3100bar and you usually go up one bar every 10 meters so they had 350bar acting on the craft, did you accidentally add a zero?

[@arturobandini4078]

I have no prior interest in this subject (deep sea exploration) but this shocking case really feeds my layperson's and morbid curiosity.

[@thindigital]

For me it's more than the usual morbid curiosity of disaster. This case is indicative of the modern scam era. A time where liars and snake oil seem to have overtaken education and virtue.

[@beehappyalways]

Same.

[@kevinm.n.5158]

Your layperson's what?

[@MattExzy]

Just as a Joe Shmuck myself, I had no idea Ocean Gate/Titan existed until the incident. Just comparing Titan with something like the DSV Limiting Factor, Titan looks like a wooden go-kart next to a Lambo.

[@KevinVenturePhilippines]

We sometimes have to follow the bizarre to learn more about the mundane. The more you learn about anything, the more you will know about everything. You are learning more about pressure for instance. Pressure is everything. Without it we couldn't breath on Earth. Everything is connected to everything else. Learn away, like a dry sponge dropped in water. You will be better off for it in the long run.

[@JelqtronZero]

i don't even think i care about this anymore, i just like your voice and the ocean pics together, its very calming.

[@soulure]

If Cockton Mush had somehow survived, I feel I can hear his dumb voice in my head during this video saying, "look at all these reusable parts!"

[@jandedick7519]

Omg your comment made me laugh . Horrible to laugh but yes I could definitely hear him saying that!

[@malena5026]

I wonder what nonsense he would testify if he wasn’t on board and had to deal with the aftermath with the incident if it just was the tourists and a crew member diving down

[@francescawilliams8177]

He would have actually believed he’s a god.

[@JuliusCaesar888]

He would blame the maintenance team and the companies who contracted with him. It would be easier to blame an entity than individuals.

[@GTAGrandpa]

They could have built a completely new titan or even a titan 2.0 from the original blueprints they made. After so many dives why wouldn’t they check the integrity of the carbon fiber? If the NTSB can go inside of the carbon fiber and see the deformations that were there, OceanGate should have been able and done the same thing one way or another. It was safe at first, but became compromised. Just a single crack in the carbon fiber would completely collapse the air pocket within the sub in an instant. RIP to everyone onboard.

[@johnshaw359]

When the entirety of the Atlantic Ocean collapses onto you in an instant, strange physics must happen.

[@askjdhagyouqgw]

Pink mist physics

[@JACCO20082012]

​@@askjdhagyouqgwnot even. Your molecules literally come apart into individual atoms. You cease to exist in the most primal way that physics has to offer.

[@Bassalicious]

@@JACCO20082012 Best description I've heard is from Scott Manley: "You stop being biology and become physics in an instant."

[@graydi66y]

Most of you. They apparently did recover some kind of organic flesh materials. ​@@JACCO20082012

[@crimpinurpimpin]

Pretty sure it was meat cloud and the densest parts like the muscle and bone and teeth may have gotten pushed into the aft dome like a paste substance. They mentioned in the report that they found a paste like substance that tested positive for the DNA of each of the people in the capsule.

[@user-wt6kg7kp5v]

I was a Oil Industry NDT Inspector I did UT and PMI (Ultrasound and Positive Material Identification). When I saw the defects and visual voids. My mouth just dropped. How did this make it out of the factory. Just the visual inspection alone is enough. I wouldn't want to be the Inspector that passed that carbine fiber to be used for what it was used for. After the BP accident we were warned heavily to double check our work before we sign off on anything. Because just like this accident people's lives are on the line with this stuff and criminal charges can be filed for negligence.

[@mercoid]

It was a toilet paper core wrapped in duct tape with two halves of a plastic Easter egg glued to either end. And people paid 1/4 million a head for the privilege get in it. Stupid.

[@Slicknicksimms87]

Lol

[@jimmyneck2854]

Not too far off in your description! Too bad all those people are dead especially the Titanic expert you think you would know better James Cameron is a filmmaker and he knew better

[@MrMississippiMan]

Lmfao 😂

[@rem45acp]

An oversized plumbus style sub is what is needed now. Everyone has a plumbus in their home, so let's make a big one with lots of schleem armor and it can do the dive perfectly!

[@huh4233]

I wonder if they found any teeth in the aft hemisphere's trash pile?

[@HVM_fi]

The green thing is one of the oxygen (or air) bottles, it's steel and red is just rust.

[@PatrickOuthier]

Rust and possibly red oxide primer.

[@TheDiveO]

they would otherwise pixelated that area if it were human remains; also, there are sharp edges to the wrinkles so this is some metal

[@YAWSSSSSS]

The fish and squid probably feasted on the Billionaires

[@charron1]

@@YAWSSSSSS Prime Wagyu Steaks for Squids

[@sunitamosesesq]

Photo was taken just days after the implosion. Don't see why there would be rust.

[@DeeEditor1]

The acoustic sensor data was very interesting to see epsecially when they layered all of them over each other. Sensor data should have been checked and compared after every dive with the previous one. Maybe it was checked and briefed by the analyst team, and Stockton simply brushed it aside.

[@green31OSU]

Assuming they had engineers in charge of the sensors and related data, hearing a loud bang should have immediately prompted them to check the acoustic data (which would have confirmed the system also "heard" the reported bang), then check other sensors around the same time to see if the event was recorded anywhere else. Had they done that, they would have easily seen the shift in strain responses occurring at the exact same time as the bang. That should prompt an immediate cease of operations to determine what was going on, since you had 1) an audible event, 2) acoustic measurements confirming the audio event, and 3) strain data suggesting the audio event was related to the stress/strain characteristics of the craft. They could have even done shallow investigative dives and confirmed the change in the strain characteristics. So either no one was assigned to monitor this data, or it was deliberately ignored.

[@champagnetina]

Your presentation and analysis is second to none. Thank you for these incredible uploads.

[@JK-tr2mt]

The message is clear. The titanium domes survived. The carbon fibre delaminated under the immense pressures. At those depths and huge pressures use titanium or some strong metal, not carbon fibre! All those previous noises on previous dives suggest that toilet roll was continually delaminating. Did Stockton ignore what the sensors was telling him all along?

[@TheDeeGeeNL]

He would have defended by saying it's the carbon fibre settling. It's clear he was such a person.

[@Beltran15x]

thed carbon fiber didnt fail, the seal around the rings changes shape under pressure at a different rate than the carbon fiber thats what created a weak point, they can both handle the pressure, but they handle it differently which created a stress point the implosion was caused by a weak spot in the front dome ring, it wasnt t he carbon fiber that failed.

[@SuperFinGuy]

The strain sensors picked up a sudden shift right when the loud noise was heard, showing that the hull was starting to delaminate.

[@dc6233]

Maybe they should have used the steel mandrel as the hull, or some tie downs around the carbon fiber. It's unreal that he wouldn't listen to anyone, he had no respect for other experts opinions.

[@johnshaw359]

He ignored everything.

[@MichielvanderMeulen]

axially bonding carbon fibre to titanium is simply crazy

[@TheDiveO]

ntsb doing the job Stockton was supposed to do: proper material analysis.

[@ShortArmOfGod]

On the taxpayers dime, of course.

[@supereliptic]

@@ShortArmOfGodwhat’s your point?

[@kutulukutu]

Meh, he probably just figured someone would eventually do it, anyway. He was right.

[@cremebrulee4759]

​@@ShortArmOfGodit's an issue of public safety. They had no power to stop what happened, but they have an obligation to determine the cause and who was to blame.

[@chrisvig123]

And worth every penny…we wouldn’t be flying jet airliners if it wasn’t for them

[@Young937phoenix]

Could you imagine paying $250,000 for your own death.

[@Alwhite1929]

Can't take it with you.

[@lenger1234]

Definitely...but if I did, I'd pick a way cooler way too go.

[@jimsmith7212]

That includes body disposal.

[@jimsmith7212]

​@lenger1234 It's pretty unique though, you gotta admit.

[@user-dg6lh2mt8g]

Best I can do is 2 dollars

[@12time12]

There’s a 300 year old Greenland shark in that area who not only chowed down on Titanic passengers, but also had whatever is left of that jerk Stockton Rush too.

[@stevemcpherson5754]

А ещё не было айсберга, был нос акулы.

[@zero1fifty8]

Wow you might be right about that but we can only speculate

[@chrisjohnson4666]

Sub brief mentioned the human remains consisted of a paste that was all the crew mixed together... I suspect there wast anything recognizable...

[@sasquatch98]

@@chrisjohnson4666I saw a comment on another video about this “it was the world’s most expensive chum bucket”.

[@EmiSuperTrans71]

Nope the Greenland shark can only dive to a depth of 2000m it chowed down on no one

[@divexplore21]

They transported the sub by towing it behind the support vessel for days, exposing all the electrics and connections to waves and weather. Even the Russian Mir subs were on deck in their own hangers for protection. Just crazy! Also, Me: What is holding the sub together? Stockton: It’s glued together. Me:…………..I’ll pass.

[@Jaded_Jester]

Add the fact that Stockton stored the Titan outdoors in Nova Scotia during the winter! People treat their canoes better than that.

[@JaceDean89]

James Cameron even said that just bringing that sub out to the Titanic site on the Polar Prince more than likely even caused stress on the haul then especially when it was on that platform being pulled behind the Polar Prince getting battered by waves. Not to mention how many dives they made in that tin can. That haul was done. I'm surprised the sub made as many dives as it did. This is what happens when you take shortcuts, you would think he would've learned from the Titanic itself.. Safety should always come first in Exploration, especially of this kind..

[@volvo09]

Hearing that they dropped it once so hard that the front nose hemisphere broke off is scary too, that's a big shock load.

[@djremotion2]

To begin with carbon is great when elongated, because the actual carbon fiber takes the stress then, but not on compression, because then only the weak epoxy is doing all the resisting into buckling.

[@richardconnelly7141]

that and opening that front access door would put alot of stress to the front titanium ring glued to the carbon fiber hull

[@Chellz801]

They were going to kill someone they just managed to make it to that day by luck and stupidity.

[@donnajarvis9542]

He didn’t care. Only thought of the money he thought he would make. I only feel sorry for the young boy.

[@beeble2003]

26:05 Not sure exactly what that guy's doing with his cloth, but he's getting his greasy fingers on one part of the titanium ring while he's wiping another part. Is that the side that gets the glue?

[@PragmaticAntithesis]

Yep, and that was seemingly the part that failed if the front falling off is any indication.

[@screw_it_why_not]

Oceangate is the equivalent of jumping off of a mountain in a wingsuit made of paper and calling it “exploration”

[@accountnamewithheld]

Was. Not is.

[@doeverything7997]

Civil Engineering student chiming in... ... from the start? Carbon Fiber is NOT the material to use for these depths... it'd be fine for someone wanting to convert their kayak into a submersible that can drop down 5-10' in a lake or along a coastline. The primary issue, as I see it, is the inherent mismatch between compression rates of the titanium rings and domes as compared to the compression rates of the carbon fiber cylinder. If both materials do not compress, or shrink, at the same rate under pressure, then there's going to be detachment where the two materials join. Ultimately I think what happened is this: Over several dives, the carbon fiber cylinder experienced expansion fatigue and ultimately delaminated (as we see in the video) but the primary point of failure was the glue connection between the ring/dome assembly and the carbon fiber cylinder assembly. They compressed at different rates, and ultimately the compression of the carbon fiber assembly exceeded the compression rate of the titanium cylinder/dome assembly, and poof.. all is lost.

[@nathanbaker146]

It's possible to taper the joints so there is a more gradual taper in the stiffness. CF could be an excellent material IF designed correctly and appropriate inspection and monitoring techniques are utilized.

[@speed150mph]

Here’s my question since you brought up compression rates. The hull was not one solid carbon fibre hull, but laminated layers glued together. All submarine hulls suffer some degree of compression. Wouldn’t the compression of each layer, each of which being a slightly different diameter, make the layers compress different and put stress on the resin holding the layers together?

[@doeverything7997]

@@speed150mph The layers of CF *could* compress differently, since they're likely not a perfect match in how the layers around them were wound, but there's something else to consider - the resin itself will ALSO compress at a different rate, unless they really did their homework and used a resin with the same compression rate as CF. What I would expect is a "cascading" effect where the different layers *may* compress differently, but they begin compressing at different points in time. Going back to my earlier post, I think it's telling that the front dome detached from the CF hull with absolutely NO carbon fiber attached - all the CF debris ended up in and around the rear dome. This looks very much like the connection between the CF hull and the forward dome is where the failure originated. If the failure had originated in the middle of the hull, then the force of the implosion would have pushed debris in both the fore and aft directions. I understand the US Navy experimented with carbon fiber submarine hulls once upon a time. Considering the lighter weight of CF as compared to steel and titanium (and what I would expect to be a vastly improved fuel economy coupled with faster speeds), I think it's telling that the Navy didn't opt to continue with CF as opposed to more standardized and trusted materials.

[@BeckVMH]

8:49 I love the shot of Rush wearing safety gear. It’s so ironic.

[@tracymetherell8744]

The “real time monitoring” DID work. Stockton just ignored the signs the hull was failing.

[@emj159753]

And also what good is a real-time system when you're thousands of feet below sea level?

[@theflyingfish66]

Didn't even need his patented acoustic system either, the simple strain gauges told them everything they needed to know. Seeing those different strain curves should have instantly sent them back to the drawing board like they did with the first hull.

[@KienDLuu]

many cases, it’s 20/20 hindsight. In this case, it’s gross negligence.

[@chrimony]

@@theflyingfish66 They didn't test to failure, so they were flying by the seat of their pants when judging how much deviation to allow. This is very reminiscent of how the space shuttles blew up. Abnormal behavior becomes normalized because it didn't fail last time.

[@infinitewars6373]

@@emj159753 it wouldn't fail in a second without letting you know, the problem is the idiot ignored every aspect of this system and kept going......

[@Cobra13645]

I'm amazed by Stockton Rush he knows that this hull can't handle going to the Titanic depths but still kept being persistent, probably if this didn't happen he'd probably kept going on seriously 😑

[@thindigital]

@@Cobra13645 the ultimate sunk cost fallacy

[@cremebrulee4759]

He would have continued until something stopped him. Legally no one could stop him, so nature and physics took care of it.

[@sheepdog457]

Delusion fed by colossal arrogance and pride.

[@MTPBUCKET]

I saw a recent quote where a life long friend of Rush said, Rush knew it would fail like it did, and when it did he knew he wouldnt survive and have to be held accountable. Certainly sounds alot like Hitlers mentality, do what i want, but disappear when i fail.

[@fridaycaliforniaa236]

It was suicide, not any random accident. Of course Stockton Crush knew it was gonna fail. But his company was in deficit, on the brink of collapse. And btw, Nargeolel was highly depressive, because he lost jis wife not long before. What better way to die to have it happen when you do what you love the most (the Titanic, for Nargeolet) ?

[@backfromcuba]

well done. this is the first decent video on this accident (post enquiry) I've seen.

[@Captaraknospider]

the carbon fiber would flex. in and out like a lung. but the end rings wouldn't. I'm guessing the carbon fiber layer near the edge of the ring got loose over time. then the fatal dive it popped.

[@normdyer94]

I agree. Any midlength bending of the carbon cylinder enjoys about 10:1 leverage at the interface with titanium. Which would certainly exceed material limits, especially at the transition to a dissimilar material where there are other stressors (thermoexpansion, bolt holes, gasketing challenges).

[@rhetorical1488]

they compress at completely different ratios. it deboned dive 1 as the composite shrinks over 1" further than the metal caps

[@mikeanderson1722]

Any woodworker will tell you that a joint with 2 materials with different expansion and contraction characteristics can't be joined rigidly or it will always fail. All it would take to cause a chain reaction was one spot starting to fail. Once the water starts getting into the joint it pries everything else loose and it's all over.

[@Elvewizzy.]

@@mikeanderson1722 But it was cheaper!

[@lohikarhu734]

@Captaraknospider; i really figured that the hugely (bigly 😂) differences in temperature coefficients, and rigidity, made for a marriage designed for divorce.

[@maegenyoungs2591]

I wonder if it was expanding under the cure cycle. And expanding the already cured layers. Under temp. That the last layer before was curing over an expanded surface. So when it cooled. It was shrinking under the last cured layer applied. I build carbon fiber cars for 8 years. And I’ve seen this before. Not in a cylindrical shape but others, The noises they were hearing were probably sheer under compression state.. The layers were failing at different frequencies. The popping was probably the bond to the peal ply layer. They were… Oh my that really was never 5” thick. It was 5 inch layers thick. I can’t believe it lasted so long. If you don’t understand what I’m saying. Take a deck of cards and split it. Then put together like your shuffling. Put the sec in one hand and squeeze.. They layers going together on top of each other in different directions. The cards sliding is the Debonding shear effect

[@katherineweber8955]

Thank you!

[@braindeadhoovy2562]

I felt it happen so suddenly when using my friends carbon tree climbing spurs, I had crossthreaded a bolt without realizing and over time under my weight the shear force popped the whole thing in a violent way.

[@DrJuan-ev8lu]

And the problem you bring up would be worse in bigger parts and can also arise where thick longitudinal layers meet thick hoop wound layers. In Titan you then stress the part to near failure multiple times. Snap, crackle ... POP !

[@bastiannenke9613]

While they did more wrong than right, i wonder what wpuld have happened if they would have looked at the deformation graphs and decommissioned the carbon fiber hull. It seems to me that its rather a quality and aging issue than a general/ unpredictable issue with the carbon. The experiences you shared here shared also speak for bad quality. If they had improved the quality each time and replaced the carbon fiber after the warnings the situation wouldn't have happened. Maybe something else would have happened, who knows. I still have to admit, that I'm impressed the hull sensors worked and successfully predicted the failure.

[@Alan_Stinchcombe]

@bastiannenke9613 Unfortunately, OceanGate had sufficient skill to fit some sensors but insufficient skill to perform real time or even post-dive analysis to successfully predict the failure. I think counting acoustic events should have been one of many metrics under validation during extensive uncrewed testing followed by dissection of the hull for analysis.

[@rekyu3d541]

such mad respect for the honest, straightforward title... the youtubey dramatization is so HORK

[@fridaycaliforniaa236]

Seven dives before the deadly one, they knew something was wrong with the sub. So, starting from this moment, every dive was attempted suicide from Stockton Crush. And he didn't even care for the passengers. Remember that pilot from the German Wings, who had no remorse when he voluntarily crashed his plane on a mountain in France, with more than 200 passengers who wanted to live ? Stockton Crush did the same thing, imho...

[@AdminAbuse]

Stockton Mush

[@elasolezito]

Different motives though. Same idiots... Same as someone who's speeding a car or train, knowing the risks "Come on nothing is gonna happen" mentality

[@LeSarthois]

I think the pilot was an egoist, But Rush was full of hubris. The simple fact that he had only real-time sensors is proof enough that he though he could bend physics to his will. What was he gonna do if his real-time sensor started to show an issue? Dive back up? In 0.05 seconds? Sounds like to me he though that a failure in deep ocean would behave like a failure in space : a leak that would leave them with X minutes to react. Or that the hull would creak and bend gently before caving in. A fool with too much money, too much charisma, and too much faith in himself.

[@elasolezito]

@@LeSarthois Isn't that the reason Titanic crash in the first place? "Ignore warnings, blind faith and trying to be the first". Our nature will never change but hell we're trying to explore the uncharted ocean depths with an xbox controller.

[@alisonwilson9749]

@@LeSarthois A pilot friend once explained to me (when showing me how to control a small plane) that in the air, at least in normal circs, things tend to happen relatively slowly- not like, say, on the road driving a car, where you can hit a wall or another vehicle in seconds if you aren't paying attention. Maybe Rush just didn't appreciate that other environments are not like aerospace?

[@maegenyoungs2591]

I’m almost starting to think. They heard something before it came.. But what is sad is that Stockton was witness to every single event of fracturing, He knew ocean gate was failing, did he just continue pulling the trigger until the chamber was empty, Leaving his mark on history, Never thinking his legacy would be that of an idiot. It’s like Jonestown, but you have to take a sub to meet your maker.

[@greencanner4284]

Nah, the carbon fiber would've failed so quickly and all at once that his "real time monitoring" would've given maybe a half a second warning if they were lucky, probably didn't even have time to process the alarm before the mighty deep took them.

[@bobbarker2726]

oh I hate the comment sections

[@tonyvelasquez6776]

@@greencanner4284 This is not disney. Yes it would have erupted violently, but they almost certainly knew they were about to die. There was likely loud sounds from delamination that happened prior to failure.

[@greencanner4284]

@@tonyvelasquez6776 Carbon Fiber doesn't work like steel or titanium does, its stress-strain curve is unique in that is has basically 0 deformation until the stress reaches permanent failure, at which point it'll fail spectacularly

[@tonyvelasquez6776]

@@greencanner4284 All of that is irrelevant when you're in an acoustic chamber a mile under the ocean. Go do some failure testing of carbon fiber in an anechoic chamber and report back.

[@karenmcculloch9428]

Hi Jeff, saw you were tuned into the enquiry each day on the live chat, your very dedicated. Cool video, cheers.

[@jeb5137]

Figure 27.... Right before the bang the strain appeared to have normalized, then the huge audio spike and at that exact moment hoop strain was slightly up but stayed there and longitudinal strain was suddenly down and also stayed there. Something suddenly shifted.

[@Defender_928]

So something stirke with titan from outside very hard?...😮😮

[@jeb5137]

@@Defender_928 I don't think something struck the titan, I think it was something stressed that snapped. Could have been layers, could have been a bolt, could have been anything. The sub is essentially a sound chamber, so a (relatively) small ping could have been amplified, especially if the equipment was attached to the sub itself.

[@CroshVine]

Their deaths may have been instant, but I would be shocked if the implosion wasn't preceded by a few scary bangs. Probably too quick to send a message, but enough to register that something was wrong.

[@88997799]

Ooh they knew it was about to happen. Not much but they knew. They dropped the weights to end the dive. So I’m guessing cracking sounds.

[@LeviJamesRE]

​@88997799 No they dropped the weights to stop the vessel hitting the sea floor! All of them weren't dropped. It was to make streering it around the titanic easier otherwise it would of just sat on the ocean floor!

[@mallk238]

The weight drops were just to slow down so they didn’t hit the grou d. They had to do that regardless of whether or not they hear any sounds. Besides, at that depth if you hear xracking that’s enough to turn around? I doubt they coulda made it back to safe depths in time anyway.

[@stevemcpherson5754]

​@@mallk238вариантов спастись больше нет в любом случае.

[@alisonwilson9749]

@@mallk238 They may have been dropping them for routine reasons, but we'll never know if there had been any noises that alarmed the crew before the final failure and that's why they were trying to slow down. With no voice recorder, we never will know. We'll also never know why a different person took over the coms at the last moment. Reports of a previous dive (the Andre Doria) do raise questions about that.

[@wendyvic4046]

You're really putting out some great videos on this, it's greatly appreciated. As a former automotive engineer, I am finding all the analysis to be absolutely fascinating! You have a new subscriber and, again, thanks for all the good work.

[@walterfredrickson3887]

I think most non technical folks like me, kneW when they showed them gluing the rings and the body together. I was like, WTF. No way you would think that would hold…….

[@eadweard.]

I believe that's what the US navy did with their successful carbon fibre sub tests.

[@TaurusMoon-hu3pd]

​@@eadweard.But the navy didn't contaminate the surface by rubbing their hand all over it before gluing.

[@eadweard.]

@@TaurusMoon-hu3pd The OP said that gluing could never work.

[@TaurusMoon-hu3pd]

@@eadweard. Yes, and you said that the navy did it. And I said yes, but the navy did it correctly.

[@eadweard.]

@@TaurusMoon-hu3pd Gluing can work fine, so the OP is incorrect. Whether the people building Titan did thier gluing improperly is an entirely separate issue.

[@fridaycaliforniaa236]

So it looks like Dive #80 was the one where all went into « cascade-mode ». And the fact the sensors were actually able to see something, this indicates this tragedy could still have been avoided. It's even easier to understand when we see the graphs at 18:08. You can clearly see that something « gave up/released tension » in the material right when this loud bang happened. If I was working there at this moment, I would have yelled at anyone to stop all of this stupid sh.t (sorry if my english is crap)

[@briananderson4032]

You got the point along just fine brother.

[@JessicaTiramisu]

It is incredibly maddening to think about.

[@v12alpine]

Exactly my thought. Every dive after that there were non-linear strain charts. I'm sure I'm wrong but it might have been the front ring starting to delaminate from the CF hull. More and more pressure is now put on the C-channel at depth and the thin titanium finally gave out. This resulted in a partial hull collapse in the front propelling everything towards the rear.

[@realulli]

I think that's exactly what the chief engineer did - and got fired over. He should thank his former boss, he's now alive and able to testify.

[@robert11751]

i think the green thing you are looking at 6:46 is one of the 4 green oxygen tanks that were stored under the floor of titan

[@Young937phoenix]

If I saw them drop this on the deck and then the front cap fell off and then I heard him say just put 4 bolts on I would say I’m sorry but im not going down y’all are a mess and are going to kill someone.

[@suesmith9202]

I hear he kept that one quiet. It got :fixed: with the 4 bolts and nothing more was said.

[@galactichazzard8932]

Pretty sure that drop on the deck that snapped the 4 bolts wasn't nice to the carbon fiber hull either. Nevermind the fact that they also towed it there to rattle it some more.

[@Knuspabrot]

That's what another commercial sub builder and pilot told Stockton after he went on one of the first dives with him. "No way are you making money with this, at least one of your four passengers is going to tell you to surface when the noises start every dive, and you'll have to refund them all." He basically accused Rush of knowing and accepting that this whole thing would end in a murder-suicide.

[@MW-xm1rc]

The only defects in the Titan Sub were the idiots who designed, then ignored the problems with it!!

[@katherineweber8955]

Thank you. I appreciate the time you take to do these videos and always learn a lot.

[@two6520]

I want to see the face of Stockton Rush when he realized oh man this is it. Well if you had time to realize that.

[@yakikadafi745]

his eyes opened wide and errybody went pop lol

[@JK-tr2mt]

He thought everything was fine. He was there a few milliseconds but gone the next. No time to think, feel or react. Instant liquification.

[@MolkoKillStyle]

Imagine ending in a five man's soup

[@kevinbill9574]

I doubt he knew anything about it... but be careful what you wish for

[@TheTotallyTori]

​@@kevinbill9574 Exactly. Monkey paw rules means you're ending up in a decompression event and get to think his last thoughts yourself.

[@Abmotsad]

“At some point, safety just is pure waste” Stockton Rush That's actually true. Problem is, Rush clearly didn't know where that "point" was. Pure hubris.

[@TorianTammas]

Using clued paper roll with metal rings on the end is not a question of safety. It is obvious insanity.

[@KarenRaver]

"At some point, my lack of safety will turn me to paste". fixed it for you

[@uhohwhy]

he wuz just a 5uicidаl sсаmmer

[@ericaknesek3266]

Thank you for this video. You did a great job trying to explain because nobody really knows how everything happened but you do put it in a way that we can at least imagine. Thank you again.

[@shmackydoodRon]

“How many atmospheres can it take?” “Well, it’s a space ship, so I’d say anywhere between zero and one.”

[@grant6173]

Carbon fiber is pretty great. But under compression, it's just thread. The whole cylinder was depending on the adhesive. Which was obviously brittle and cracking more all the time..

[@wattage2007]

I thought that all along. They would've been just as well making a 5" thick hull using toilet paper and adhesive.

[@jpdemer5]

@@wattage2007 A cast epoxy hull would fold under the pressure, but the deformation would involve stretching on the outer circumference of the folds. To the extent that the carbon fibers resisted that stretching, they contributed strength.

[@grant6173]

@@jpdemer5 Pretty much. The carbon fiber was just along for the ride. Super great for someone trying to raise money. Really hits the hype.

[@abn82dmp]

Kind of like pushing a rope....

[@major__kong]

It's like pushing on a rope until you put it into a matrix. Then it can take compressive loads. The matrix prevents local buckling of the fiber. Modern aircraft wings are made of carbon fiber composite, and the upper wing skins take significant compressive loads and don't fail. But I'm guessing Boeing and Airbus have better manufacturing processes than these guys.

[@denisecaringer4726]

What a superbly detailed and explained look at what happened. I always appreciate your work. Thank you.

[@gabriel7664]

Hands down, this is the most informative video I have seen about the Titan report. Nearly every other video is an a.i narrated video, and they all show the same pictures and say the same things. They are all clones. You did an awesome job analyzing the material etc. This video is the most professional video I have seen about the Titan report. Good job bub 👏 👍. You have been very thorough.

[@maynardlikethecandy5347]

It was crazy to transport, store, move, the Titan while on land, without extra support for the titanium ends. Those pieces are very heavy, and with constant gravitational downward force amplified when bumped. That is a lot of strain on the glue.

[@JK-tr2mt]

And then the immense deep sea pressure! No chance!

[@wattage2007]

And the forward titanium dome fell off after a mission once. That glue joint never stood a chance with the abuse it was getting.

[@briananderson4032]

I have wondered about that. With the domes weighing in at 3,500 lbs, and that weight was concentrated on the hinge, even though there was a dolly used to hold the weight of the forward dome when opening and or closing, it was reported that at one time, the forward dome fell off of the submersible, while under tow in rough water. That seems to me there would be some kind of damage from that type of incident.

[@LatitudeSky]

They took almost NO care of the machine. They stored it outdoors in a parking lot stacked on old wooden pallets, they dragged it behind carrier ships, they shoved into box trucks and hauled it around. Absolutely no gentle handling. They treated it like a borrowed lawn mower they weren't going to give back.

[@Malibus_Most_Wanted]

Also they could have glassed in the ring with carbon fiber but also he ingnored the fact carbon fiber can only be flexed/compressed only so much before failure. No ndt done on the hull also not building it even thicker than what you intended to use it for. Carbon wheels n scba tanks have a shelf life for a reason. He was warned about this but ignored it aswell

[@averyhy]

Thanks for keeping us updated

[@cremebrulee4759]

If Stockton's "real time" monitoring system was as good as his vessel, it was worthless.

[@01pantagruel]

Well, it appears to have successfully recorded a problem, so a component of this would be "a monitoring system doesn't do much good if you don't pay attention to what it reports".

[@fridaycaliforniaa236]

In some ways, 8 dives befores it showed that something was about to happen. So maybe if someone tried to look at the sensors data, the accident could have been avoided...

[@Itsjustme-Justme]

Watch the video. The monitoring system gave alarming data. The technology worked. It correctly predicted death. They simply ignored it.

[@Kowalski301]

The fact the vessel even had a "real time monitoring system" was perhaps the biggest red flag of it all! A vessel like this should have no need for any type of hull monitoring beyond unmanned pressure testing. And as far as i know, no other submersible have any type of hull monitoring installed.

[@bluedistortions]

They didn't really even need a monitoring system. Everyone who set foot on that sub and survived said it sounded like rice crispies getting wet when it dived, so it was delaminating constantly. It's only a question of which of Stockton's many cost cutting measures were the most relevant. But yes, it's especially stupid to brag about this early warning system that he never paid attention to.

[@thindigital]

Very interesting comments on the strain gauges, i imagine if someone showed Rush he would have ignored it. He knew it was unsafe, to my mind he didn't think he would be pilot for long and someone would be hired, Lockridge testified to being asked to pilot and Rush was stunned when he said no way.

[@briananderson4032]

Not only No Way,,,, no fuckin way,,,,

[@gerdplume5544]

But still took the munee, they all to blame including the passengers. A lot of very smart people come out the laminate after the fact. Where were ya all b4? In all honesty it's just amateur hour all round and I actually feel the craft done very well to do so many dives considering it's inherant faults. Stockton liked living close to the edge, could have scratched the ich with less collateral doing summit solo. WAC.

[@jeremypnet]

He would have pointed to the fact that the lines were still straight at the deep depths and claimed that made it ok.

[@jaylemeux]

do you have a timestamp for that Lockridge remark?

[@alisonwilson9749]

@@gerdplume5544 Lockridge tried to raise it with the authorities. He says that the authorities delayed and delayed and then Oceangate tried to sue him, and so he had to give up.

[@loc6880]

Thanks For This Video! You do the best production on, and analysis of the Titan Tragedy..

[@PorkchopXpress]

Apparently when the wreckage was brought up, they found a paste type substance that had human DNA. Makes me cringe thinking about it.

[@sparky4878]

What I heard was they inspected the “paste” and it contained the DNA of all five people.

[@hannahbeanies8855]

@@sparky4878makes sense…I guess they all got “smooshed” together…for lack of a better term. Absolutely awful.

[@NealD]

Yea all of them are inside of that dome.

[@nerdygem8620]

How do you return remains to the families in that situation? Divide it into fifths? Or if no remains are returned, how is it disposed of? You can't just scrape remains into a laboratory bin, there are rules about respectful handling. Would they be cremated as a group?

[@gregorsamsa5251]

That's actually surprising to me - I would have thought with such a violent implosion even the DNA strands would break apart

[@kennybobby201]

The first sign of trouble was whenever the engineer started this terrible design.

[@ProfNimrod]

Hmmm, not sure about that… you could argue that the design was OK, as long as it was recognized that it would be safe for no more than, say, 10 dives, or something like that.

[@sshreddderr9409]

the problem isnt the engineer, the problem is Stockton trying to build a submarine with a greater carrying capacity than previous subs with a fraction of the budged, and then committing to it like his life depended on him carrying 5 people to the titanic by any means necessary. the whole idea of commercial deep sea diving is a terrible idea. the danger and complexity involved naturally forces a ridiculous price per seat, which nobody would be willing to pay. his sub probably cost 1/1000th of what a well designed sub would have cost to build, which greatly lowered the price per seat, and he still had trouble getting people on the thing especially once they got a feeling of the sub and the whole operation of the company.

[@kennybobby201]

@@ProfNimrod this was dive #88. Go watch the interview of james cameron talking about the use of carbon fiber for deep sea subs. If the design doesnt match the intent, the problem started at the beginning.

[@kennybobby201]

@@sshreddderr9409 if the design doesnt match the intended use, your problem started at the beginning. However you got there is up for debate i guess. I agree it likely had to do with finding a way to make this business successful, cutting corners to do so.

[@sassafras710]

@@kennybobby201 "The design didn't match the intent" spoken like a true armchair engineer. You backseat drive too?

[@ditdot151]

I really enjoyed watching this and thank you for all the work you put into it. By the way that is one beautiful watch you have!

[@Maven1999]

I'm betting the curve on the strain gauge after 80 was representing deamination. That curve is probably the layers of carbon being pressed back together at the outside pressure increases.

[@alisonwilson9749]

Sounds plausible, at least.

[@renevanderkraats224]

@@alisonwilson9749 I was thinking the same.

[@charletonzimmerman4205]

Skipped Inspections, it was a "RUSH", JOB !

[@WillSing4TP]

Where's a rimshot emoji when you want one?😂

[@briananderson4032]

Jesus, you sick bastard…. That was great. 😂

[@Tylnorton]

Stockton Crush

[@lilyw.719]

​@@briananderson4032 Blessed be Jesus's holy name. It's not a curse word.

[@glenncooper3524]

16:25 when I heard Stockton say they only ran the CF circumference and longitudinal cause there's no torque in water which I don't believe. I thought, what about out of the water? The employee that helped recover the wreckage thought dragging on deck and towed where both really bad. And when the RTM system picked up large spikes from being dragged on deck didn't matter. Holy crap and the dome being sheared off that had to be devastating to the hull CF and glue joints and rings!!!!!!! The rhino liner was stupid on a epic level. Or was it Stockton not wanting the outside inspected. What I completely think. Like an ostrich sticking its head in the sand.

[@DavidG2P]

This shows why you don't use fiber composites for COMPRESSIVE loads

[@SkyCuration]

Yes, it's the exact Opposite load.

[@major__kong]

Boeing and Airbus might want your expertise. They regularly build composite wings. The upper wing skins are under significant compressive load. You can help save thousands of airline passengers' lives with your knowledge.

[@askhams]

The fibre weave is almost irrelevant in comprehension - you're just relying on the resin. The weave is like an empty bag, full of air, but with a gaping hole. It's just not going to hold it's shape. In which case, would you make a pressure hull from resin? It's so bloody obvious - it's painful

[@zemm9003]

​@@major__kongno they are not.

[@RideAcrossTheRiver]

@@major__kong Wings flex, you dolt, and are not a hull.

[@LD-qj2te]

Pretty clear that the composite failed . No doubt about it . Glued together . Different thermal expansion and compressive properties. Composite was not cross lapped or woven or glued . Expansion and contraction plus delaminating and bad glue bond - failure is inevitable

[@phylliswurm9473]

Definetly instills anxiety watching what happened. Good narration. Thank you.

[@tomjames137]

The Rhino liner! "The Military use it" SR's own words in another interview. I can see most survived. Ok stockton, il give you that one! The green thing that looks like blood on it i saw was discussed on reddit. Turns out it might be the oxygen tanks from another angle photo but they are just squished beyond recognition. Such a nasty way to go, but would of been instantaneous.

[@HoosierDaddy_]

I just keep thinking about that Rhino Lining. It has to be a petroleum based product and I just can't help but think it wasn't a good idea to put that on the submersible. It may not be a root cause, but I sure don't think it helped. This whole thing looks sketchy to me.

[@SchindlersFiist]

"Rhino liner" sounds made up 😂😂😂😂😂

[@localbod]

You are right. It would have been so quick that their brains would not have had time to register it happening.

[@Vermilya]

@@SchindlersFiistit’s a truck bed spray in rubber liner. Been around for 20 years I’d say. Some people spray their whole vehicles in it, especially ones for hunting

[@kisstune]

@@localbod So long as there wasn't issues on the way down etc then they wouldn't know

[@brunonikodemski2420]

Second comment. From prior submarine failure information, I believe that the structural failure started at the forward dome, BUT that the dome acted as a partial "piston" which pressed a "zipper fault" along the fiber, and compacted it all forward. Then I believe the cavity "dieseled" and blew the forward dome off, and also blew out the window in it. Did they ever find the window? It would tell a story in itself. Our company did the DOWB submersible, and dieseling was common where there was an Oxygenated cavity, with organic or combustible material in it. This sometimes occurred at only 2000psi pressures. At their 5000-to-6000psi, this was sure to occur, at least in small cavities.

[@DrJuan-ev8lu]

And I bet there us a big flash. I wish you could testify at the hearings !

[@katherinegenovese10th]

wonderful breakdown video. It’s like you were reading my mind last night because that was my first question and you are just answering my questions to the t

[@SAOS451316]

It's technically possible to build a carbon fibre hull for those depths, but to make it safe would be more expensive than just using titanium to begin with. If Mr Mush had any sense he could have built an Alvin clone for not a large amount of money in billionaire terms, and have a vehicle that lasts a lifetime.

[@jackdbur]

No Alvin had a series of hull spheres during its lifetime! 😮 its designers were cognisant of even Titanium having a limited lifespan under such pressure.

[@SAOS451316]

@@jackdbur Of course the pressure cycles take a toll on any part but Alvin is repairable and a reliable design. It's also equipped with numerous instruments and is a whole lot safer, more comfortable, and self reliant than the Titan. The Titan is like a scaled up version of a mini submarine I made for a school science project decades ago, and I wasn't exactly a certified engineer then.

[@loverainthunder]

He was too smart for the facts, sir.

[@kennbmondo]

​​Accidents involving Delta -p are the stuff of horror movies.

[@fridaycaliforniaa236]

Dont under-estimate Delta-V, mate ^^

[@bachtube11]

Wow, thats really detailled and clear photos, good information!

[@BD12]

It's been confirmed in the inquiry that Stockton Rush used to shout his own name during sex, and he had one of those big wall mirrors installed in his penthouse. "Come on, Stockton! Yeah, big guy! Who's the best sub pilot? Who's the best SUB PILOT!".

[@2QRh6g1I]

Somewhere shoved into the aft dome, along with all that carbon fiber debris, are 5 sets of DNA...RIP

[@jackdbur]

Part of the carbon fibre tube gave way and allowed the front dome to move rearwards smushing a lot of the hull into the rear dome then it rebounded off. The occupants would have been paste before their brains could have comprehend anything.

[@hiha2108]

It's hard to imagine what 300kg/cm² in a depth of 3000m are. In the combustion chamber of a diesel engine are 50-60kg/cm² when injected Diesel fuel ignites autonomously. The combustion-pressure after ignition is about 150kg/cm², the halve of the pressure outside the Titan-submersible in that depth...

[@moso00]

Didn’t see anyone mention: implosion, compression and ignition explosion is repeated with a specific frequency and dwindling intensity. This sound was the first confirmation of what happened and at what depth.

[@nobiazcustomsinc5030]

That loud bang was absolutely the 1st big "pop" of delamimation/glue failure. Why they chose carbon fiber for a pressure vessel is beyond me. After watching the build video it amazes me how unsteril the build area was. people handling mating surfaces with bare hands, etc. Could it be that the carbor fiber layers were so poorly glued together that the pressure of the deep sea caused the glue to finally grab and then as they surfaced it let go again due to the lower pressure towards the surface?

[@scotbotvideos]

Sounds plausible.

[@DrJuan-ev8lu]

Not the first, but probably one of the last and biggest.

[@nobiazcustomsinc5030]

@@DrJuan-ev8lu Smh that was the sound of doom for sure

[@nobiazcustomsinc5030]

@@scotbotvideos It occured to me after seeing the uncured glue in the photos smh. The whole process of assembly that carbor fiber cylinder was doomed from the start smh

[@scotbotvideos]

@@nobiazcustomsinc5030 Yeah, it was a calamity from conception.

[@marvtomson574]

the green things at 6:45 are actually the oxygen tanks that were underneath the floorboard.

[@zakiranderson722]

Yeah I came back here to answer that question after I found out from another vid. I assume the reddy color is rusted where the paint go pinged off. Very recognisable when we're told what it is. Amazing.

[@volvo09]

Those tanks are so strong (and it had hundreds or a thousand PSI of pressure in it) and it STILL got crushed and bent like stepping on a tin toy.

[@bigfootape]

Beyond a certain point, quality control on your carbon fiber pressure hull is just pure waste. - Stockton Rush, probably

[@bushgreen260]

*They turned off the RTM system on the previous two dives before the fatal dive. Maybe it would have shown increase strain on those two dives, giving them a warning of an incoming Implosion. It was probably off on the fatal drive aswell. How silly of Stockton to switch it off.*

[@SchindlersFiist]

JEFF! Fix your last video! It goes black a quarter way through! 😢

[@fridaycaliforniaa236]

His last video imploded

[@ryanhallyyc]

thank you for this video. the more I learn about this sub, the more shocked I am that anyone felt safe in it.

[@safa4786]

Plz explain how they got the wiring into the sub( from outside). How would the seal maintain the integeity of the holes.?

[@emjay9280]

Blu-Tac.

[@subadanus6310]

why go through the hull when you could do it with a strong wireless system with the transmitter and receiver directly atop each other on the inside and outside, or better yet, just use your two titanium dome ends as positive and negative

[@soulure]

I'm also curious about this but assumed it went out through one of the end caps.

[@fridaycaliforniaa236]

The wiring went through the rear titanium dome, if I remember right

[@rockothepig]

@@fridaycaliforniaa236so what seals that?

[@alayneperrott9693]

Thank you for this insightful analysis. The photos released by NTSB suggest that the Titan 2 sub failed near the forward end, ramming a lot of the debris aft. This suggests 3 obvious possible causes: - A major delamination event starting at the frayed end of the carbon fibre hull, resulting in the unexpectedly large fragments A, B and/or C. - Failure of the epoxy bond between the carbon fibre and the titanium ring. - Failure of the "non-standard" acrylic viewport as suggested by Mr Kemper. Just my suggestions. There are probably more.

[@BlueSpruce2]

If the viewport failed it would likely have exploded from the inside out instead of the implosion we see. I think you are right it failed at the front - quite possibly near the titanium ring. I would like to see more detail on how the forward door was hung from that ring or the frame as opening and closing it could have resulted in weakening of the ring bonding to the carbon fiber.

[@alayneperrott9693]

​@@BlueSpruce2 I agree, not what you intuitively expect for the viewport, It was a "non-standard" design, not certified to the correct depth. Rush used a cheap one made in Europe because the quote from the experienced US company Hydrospace was too expensive. Kemper testified that the acrylic viewport was observed to bulge INWARDS on each dive, which agreed with his own stress-strain analysis, although the observed inward movement was significantly larger - red flag! I note that the acrylic window has not been found on the ocean floor, just the forward titanium dome that housed it....

[@BlueSpruce2]

@@alayneperrott9693 Maybe not surprising as it is clear and relatively light and small to begin with so it could be there or blown further away outside of the debris field. If it was being distorted well beyond what a finite element analysis model indicated then they should have stopped and questioned the material or application since they were relying on the external water pressure to seal and hold it in place. Personally I think the failure occured at the forward titanium ring C-channel to carbon fiber interface. I would have liked to see a much of longer or deeper channel supporting the carbon fiber cylinder at the ends. Finally the way the carbon fiber was wound makes me think the only real strength came from whatever resin they were using to bind the fibers together - prepreg or otherwise.

[@alayneperrott9693]

​@@BlueSpruce2 I agree about the vulnerability of the glue at the carbon fibre/titanium join. The NTSB report is very cagey about their data on the state of the titanium ring, because they don't want to speculate at this point. But very little remaining glue was visible on the forward as opposed to the aft titanium surface. I am wondering whether the bang after Dive 80 was the start of a major delamination event, letting water into the forward seal.

[@BlueSpruce2]

@@alayneperrott9693 That is quite possible whether it's carbon fiber pressure vessel layers or the bonding interface of said vessel to dissimilar materials. Most of the glue was probably sheared off in the implosion. The flanges of the titanium C-channel on the forward ring indicate shearing failure. The NTSB and Coast Guard are likely holding back a little because they want to hear more from the people involved in the engineering and those who worked on the assembly and testing, such as it was, of the submersible. But I think they know, or have a working theory, how it failed. An experimental vessel like this really should have been designed for complete ultrasonic testing of the entire assembly (Ti and Carbon Fiber) after every dive.

[@robshowtos478]

Thank you! Fantastic analysis, as usual.

[@jpdemer5]

The glued joints, where the titanium and composite were expanding and contracting at different rates with every dive cycle, is what would worry me most about the structure. That sheared-off inner flange (see @26:15) of titanium might represent the actual failure point: it was awfully thin, and it would have been subjected to the full external pressure (transferred by the compressing hull) if the glue let go. (There's not a trace of epoxy adhering to the titanium rings in the wreckage.) The acrylic window was immensely strong, and could not have been forced in through its conical seat. It was likely blown out, and is probably sitting intact on the sea floor. It will be hard to see, given the refractive index of the salt water around it.

[@michaelfoster-qw2tw]

Hey JP. This diagram, I assume as built, and your analysis explain it all. Videos of the mating process between flange and hull suggest a slip fit, lubricated by the epoxy. That means some no-doubt slightly undersize CF, and slightly oversize c-channel. As the hull compressed, it would put great strain on that "awfully thin" inner flange, while trying to pull away from the outer flange; not ideal for any rigid epoxy. And the sliding deck of cards effect would adversely affect the "adhesive butt joint". My FIRST draft of such a joint, ignoring the differential rates of compression, would include the channel being at least as deep as the width, and the inner flange several inches thicker. But that stress riser at the bottom of the channel would still be an issue, not to mention the fracturing epoxy. If there was a way to make some kind of morse taper on the CF and the mating surface... I would test that. Or maybe just make the whole thing of titanium... Thanks.

[@cyphi474]

I think window was just shot out under sudden inner pressure blow. It shouldnt be very far.

[@ryancraig2795]

Apparently the company that made the window predicted cyclic failure if used at this depth. But as the retaining ring for it was missing when the done was retrieved, it does seem likely that it was blown out and was not the origin of the implosion.

[@SkypowerwithKarl]

I’ve worked with carbon fiber. Any attachment has to have a gradual transition that’s feathered or ramped strain relief section. That “C” channel or groove around the titanium dome and ring are much too shallow and the thickness of the edges are way too thin. The titanium and the carbon fiber body will have a size reduction as hull pressure builds. The rate though small must be exactly the same between the two materials. If one side is stronger(thickness) than the other, the stress at the junction will be unimaginable and lead to certain failures. The graph of the strain gauge should have been more linear and curved. Those spikes seen are noise or an anomaly. Pizzo electric microphone on the hull could have picked up the signature of fiber strands failing. That type of instrument would have shown spikes as those on the graph. Any time you build something like this it must be brought to a test depth (not rated depth) for many cycles and time and then a crush depth to failure (sacrificed) before anyone is allowed in the working machine. This is expensive but looks at the cost now.

[@henkspui]

Thanks for yet again a super upload 🇳🇱👍

[@deltasyn7434]

His sub design is way too expensive to have nearly every single component be so poorly made. Seeing as he had zero intentions of doing anything right, he should have saved his money and used rhino liner. That man was all about money at the end of the day.

[@epincion]

One example of Stockton Rush’s attitude was that he bought the raw carbon fibre second hand from an aircraft manufacturer (Boeing I believe) - it was cheap because it had expired

[@jeldraws3854]

It wasn't "poorly made" otherwise it would not withstand a single dive. Still not a good design idea

[@deltasyn7434]

@@jeldraws3854 It was poorly made simply from manufacturing standpoint. IDK what your logic is. The sub was intended for much more than one dive.

[@jeremypnet]

Not expensive enough.

[@jeldraws3854]

@@deltasyn7434 yes and it withstood also a lot more dives than one. I wonder how you would see if it was "poorly made" without being involved in the process. I agree there were bad decisions made but its not like they forgot some screws or did not reach the construction quality they've intended to build

[@jadedlotuz5095]

Thoughts. The green thing (ca 9 min in), I've heard some speculate is one of the Airtubes (used to be located under the innerfloor in the front). The "Crack" on Section B (ca 12 min in), isn't a crack, it is one of the outer railings that twisted. Cheers.

[@BruceandRobin]

Hey Jeff. Thanks for the video. FYI it repeats at 8:28

[@Garth2011]

Seems as though Stockton's "experienced" engineers failed to understand how 5 layers of autoclave and an adhesive between them doesn't work out. I'm no engineer however, I wouldn't trust 5 autoclave sessions for the total 1" layers as effective. No matter what you do, each layer is going to be independent of each other which means the pressure is not going to be shared with the total hull but rather by each layer which is probably weaker design. When that imploded, the weak portions caved in, the bottom remained while the air pressure created during the implosion shot the front hatch off into the distance. I noticed even those bolts that secure the end caps are totally missing from the ring and none of the adhesive on the ring held to the carbon fiber hull. All of those college employees should have said a test at depth should have been done before allowing humans to go inside.

[@jeffostroff]

supposedly the manufacture insisted they do multicures

[@coachwendy5618]

He had real engineering advice that he refused to follow because he was more greedy than cautious and he coaxed paying customers into believing it was safe. They should have taken the fine print writing in their contract more seriously.

[@Garth2011]

@@coachwendy5618 Oh so true. I'm just suggesting even those college kids would have followed sound advice.

[@Garth2011]

@@jeffostroff Well now they know that doesn't work. I would not have agreed.

[@Csharpflat5]

So basically one layer cooked 5 times one cooked 4 times… wow what could go wrong.

[@solemnpeace8834]

Great work thanks

[@MistyHosier]

Thank you for this. I have zero knowledge about any of this but I was able to easily follow your explanations and understand better what may have happened. Thanks again.