Titanic tourist submersible goes missing with search under way

[triplets_93]

 

[Pass2Run]

A lot of good discussion around carbon fiber but I wonder how much we really know. From what I have read, carbon fiber is stronger and more durable than steel. And not just by equivalent weights. But it is also less dense (hence the lighter weight).

Watch this video:

It is hard to imagine a drive shaft made of such a light material being stronger than steel, especially under torque, but it is. Of course the Titan was not dealing with torque, but still the carbon fiber is incredibly strong.

But what does this mean? There has to be more to it. Was the shape of the Titan a problem? A ball would be stronger than a tube, wouldn't it? What about the possibility the Titan hit something and suffered damage to the hull before the implosion? My physics is a little rusty but what about the effect of the density of the water on the carbon fiber tube? CF has a high tensile strength but its compression strength can be as little as 10% of its tensile strength.

I have to believe people a lot smarter than me looked at all this before they dropped that thing in the water but I am very curious. I wonder if they will attempt to recover the pressure chamber to see if they can figure out what happened.

The issue, imo, was the window. I'm unsure but I think it was made of plexiglass. When they dove down, Rush said the window would compress inward about a quarter inch. The window was only approved for 1,300 feet.

I don't understand the need to go down to Titanic when we already have video of the site. I think Rush was just greedy and wreckless with other people's lives.

He also knew there was cracking at certain depths. He could hear it, according to his friend.

 

[Robbieac]

I don't understand the need to go down to Titanic when we already have video of the site. I think Rush was just greedy and wreckless with other people's lives.

With that mindset….

Why do anything in life? Why go to the Grand Canyon? Why go to Niagara Falls? Why go to a Cowboys game? They have video of all of this already.

We should all just sit in our homes and watch youtube documentaries. Go out and doing things is just WAY too dangerous!!

 

[Rockport]

The issue, imo, was the window. I'm unsure but I think it was made of plexiglass. When they dove down, Rush said the window would compress inward about a quarter inch. The window was only approved for 1,300 feet.

I don't understand the need to go down to Titanic when we already have video of the site. I think Rush was just greedy and wreckless with other people's lives.

He also knew there was cracking at certain depths. He could hear it, according to his friend.

Because you would be in a submarine at 1600 ft looking at the Titanic.

 

[gtb1943]

With that mindset….

Why do anything in life? Why go to the Grand Canyon? Why go to Niagara Falls? Why go to a Cowboys game? They have video of all of this already.

We should all just sit in our homes and watch youtube documentaries. Go out and doing things is just WAY too dangerous!!

You want to die stupidly be my guest.

 

[Warick]

Here is a video made by a YouTuber that was supposed to go on the sub.

 

[Creeper]

The issue, imo, was the window. I'm unsure but I think it was made of plexiglass. When they dove down, Rush said the window would compress inward about a quarter inch. The window was only approved for 1,300 feet.

I don't understand the need to go down to Titanic when we already have video of the site. I think Rush was just greedy and wreckless with other people's lives.

He also knew there was cracking at certain depths. He could hear it, according to his friend.

Once they recover the remnants of the sub they will be able to determine pretty quickly if the window gave way. But it does not shock me that under pressure the window bowed in a little bit, even 1/4 inch. High rise buildings sway several feet in the wind and engineers can account for that.

I read the story about the cracking noises on a previous trip but I am not sure that would be unusual for carbon fiber. Consider that carbon fiber is actually tiny fibers of carbon atoms that overlap. These are woven into sheets which are overlapped to form the rigid 5 inch think pressure chamber. I would expect to hear some cracking as the pressure compressed the chamber even a little bit. But I admit I am not an expert.

 

[Pass2Run]

With that mindset….

Why do anything in life? Why go to the Grand Canyon? Why go to Niagara Falls? Why go to a Cowboys game? They have video of all of this already.

We should all just sit in our homes and watch youtube documentaries. Go out and doing things is just WAY too dangerous!!

Because Rush was misleading people about the level of safety saying it was as safe as crossing the street because that's how he made money. People would back out, he'd double down on how safe it was an lower the price.

For him to do it, fine. But taking some niave kid down with him was a crappy thing to do. I know he knew it wasn't safe

Why didn't he want to go through safety inpections? Because he knew it would not pass...

Dude was a greed sack, IMO. He knew the think was cracking...

 

[Pass2Run]

Once they recover the remnants of the sub they will be able to determine pretty quickly if the window gave way. But it does not shock me that under pressure the window bowed in a little bit, even 1/4 inch. High rise buildings sway several feet in the wind and engineers can account for that.

I read the story about the cracking noises on a previous trip but I am not sure that would be unusual for carbon fiber. Consider that carbon fiber is actually tiny fibers of carbon atoms that overlap. These are woven into sheets which are overlapped to form the rigid 5 inch think pressure chamber. I would expect to hear some cracking as the pressure compressed the chamber even a little bit. But I admit I am not an expert.

I'm not an engineer either. But I know enough that binding materials was probably not a great idea, same for using carbon fiber. It's great for bikes...airplanes, etc. But the way it cracks when wrecked ..just doesn't seem wise to use in subs.

Other subs like this use nickel and other kinds of metal..

 

[nate dizzle]

With that mindset….

Why do anything in life? Why go to the Grand Canyon? Why go to Niagara Falls? Why go to a Cowboys game? They have video of all of this already.

We should all just sit in our homes and watch youtube documentaries. Go out and doing things is just WAY too dangerous!!

None of those things is like this thing. Not even in the same galaxy as this thing.

 

[Vtwin]

The first two men that went to the bottom of the Mariana Trench had the viewport in their submersible crack. That was approximately 3 times the depth of the titanic.

They believe the USS Thresher imploded at about 2400 ft when things went wrong during its sea trial while testing its operation at max rated depth of 1300 ft.

 

[Robbieac]

None of those things is like this thing. Not even in the same galaxy as this thing.

It’s all about perspective.

Some people think you shouldn’t ride a zip line. Or go parachuting. Or go in a hot air balloon, etc…
Unnecessary risks they might say.

But there have literally been 100s or thousands of these submarine journeys and explorations. The passangers had every reason to believe that it would be safe like all of the previous times. To them it wasn’t an unnecessary risk at the time.

 

[Creeper]

I'm not an engineer either. But I know enough that binding materials was probably not a great idea, same for using carbon fiber. It's great for bikes...airplanes, etc. But the way it cracks when wrecked ..just doesn't seem wise to use in subs.

Other subs like this use nickel and other kinds of metal..

I would like to understand more about "fatigue" with carbon fiber. It is true, when carbon fiber fails it shatters while steel and other metals bend or break. But that does not mean it is not strong enough to withstand the pressures of the ocean depths if it is used correctly. All materials experience fatigue. But from what I am reading, CF fatigue is a more acute problem with subs than with steel ad other metals. Maybe the rigidity of CF is it's flaw.

 

[Creeper]

I'm not an engineer either. But I know enough that binding materials was probably not a great idea, same for using carbon fiber. It's great for bikes...airplanes, etc. But the way it cracks when wrecked ..just doesn't seem wise to use in subs.

Other subs like this use nickel and other kinds of metal..

Right, but did you watch the video I posted showing the testing of steel and carbon fiber drive shafts? The CF drive shaft withstood much more torque than the steel drive shaft despite the fact the CF shaft was significantly lighter in weight. It is not how the material fails, it is when the material fails that matters. Also, note the CF shaft did not fail at the connections to the metal end caps. The CF itself failed. Now torque is not the same as a compression force but it is still a good demonstration of the strength of CF.

I saw one video of a guy claiming to be an "expert" on subs and he made the point that the shape of the Titan was the result of designing for paying passengers. Design accommodations were made to allow 5 people to take the ride. I assume the window was also designed to give those passengers a good view of what was outside the sub. The longer pressure chamber made the sub more vulnerable in the middle. Again, this does not mean it was doomed to fail. They could have designed it and built it to be strong enough despite the length.

We are all speculating as to what the problem was, but we will not know unless they can recover the pressure chamber. And that might be in pieces all over the ocean floor.

 

[Vtwin]

I would like to understand more about "fatigue" with carbon fiber. It is true, when carbon fiber fails it shatters while steel and other metals bend or break. But that does not mean it is not strong enough to withstand the pressures of the ocean depths if it is used correctly. All materials experience fatigue. But from what I am reading, CF fatigue is a more acute problem with subs than with steel ad other metals. Maybe the rigidity of CF is it's flaw.

The structure of any type of fiber mat material, such as fiberglass or carbon fiber, is much stronger when the pressure is trying to stretch the fibers rather than collapse them.

Force applied from the inside of a tube is trying to stretch the fibers. Force on the outside is trying to collapse them.

I am certainly not an engineer, although I do have my certificate of completion from the prestigious Beull's Gore School of Redneck Engineering.

Questioning that aspect of the engineering behind the layup of that hull would have been my first question. if I was there when it was being done. I bet the epoxy itself provided as much strength as the CF in that configuration.

 

[gtb1943]

It’s all about perspective.

Some people think you shouldn’t ride a zip line. Or go parachuting. Or go in a hot air balloon, etc…
Unnecessary risks they might say.

But there have literally been 100s or thousands of these submarine journeys and explorations. The passangers had every reason to believe that it would be safe like all of the previous times. To them it wasn’t an unnecessary risk at the time.

Defending stupidity is not about perspective.

Idiotic risks are idiotic risks.

One could argue about this but it seems rather clear that anyone that took a good look at the sub and everything around it was a FOOL to go on it at best.

 

[Pass2Run]

Right, but did you watch the video I posted showing the testing of steel and carbon fiber drive shafts? The CF drive shaft withstood much more torque than the steel drive shaft despite the fact the CF shaft was significantly lighter in weight. It is not how the material fails, it is when the material fails that matters. Also, note the CF shaft did not fail at the connections to the metal end caps. The CF itself failed. Now torque is not the same as a compression force but it is still a good demonstration of the strength of CF.

I saw one video of a guy claiming to be an "expert" on subs and he made the point that the shape of the Titan was the result of designing for paying passengers. Design accommodations were made to allow 5 people to take the ride. I assume the window was also designed to give those passengers a good view of what was outside the sub. The longer pressure chamber made the sub more vulnerable in the middle. Again, this does not mean it was doomed to fail. They could have designed it and built it to be strong enough despite the length.

We are all speculating as to what the problem was, but we will not know unless they can recover the pressure chamber. And that might be in pieces all over the ocean floor.

When the window was approved for 1,300 meters and they're at 4,000...safe to assume it might have been the window.

Might is maybe, so maybe not...

I would say it's important to ask why military subs don't have any windows...

 

[nate dizzle]

When the window was approved for 1,300 meters and they're at 4,000...safe to assume it might have been the window.

Might is maybe, so maybe not...

I would say it's important to ask why military subs don't have any windows...

My guess would be that intentionally installing a weak point that could turn the sub into a smashed soda can so the troops could look at the fishies seemed like a bad idea.

 

[Pass2Run]

My guess would be that intentionally installing a weak point that could turn the sub into a smashed soda can so the troops could look at the fishies seemed like a bad idea.

I don't think bad idea was in Stockton Rush's vocabulary. Legacy admission into Princeton. We had the same issue with our former Dear Leader and Princeton alum, Mr. Clapper.

All ideas are good.

All of our players are good.

Conclusion? Don't send your kids to Princeton.

 

[Pass2Run]

My guess would be that intentionally installing a weak point that could turn the sub into a smashed soda can so the troops could look at the fishies seemed like a bad idea.

Think about it..millions of pounds of pressure on that thing. 6,000 lbs per square inch!