Another way to look at it is concrete as an example, the bizzarro carbon fibre. Concrete has good compressive strength but sucks at tensile. We add rebar or mesh to improve tensile.
Concrete is like the epoxy, and the rebar like the CF. But for the record I will also take a hard pass on a concrete submarine....
Another way to look at it is concrete as an example, the bizzarro carbon fibre. Concrete has good compressive strength but sucks at tensile. We add rebar or mesh to improve tensile.
Concrete is like the epoxy, and the rebar like the CF. But for the record I will also take a hard pass on a concrete submarine....
If it is going to be a tourist attraction they might as well just cut to the chase and raise the ship and put it on Clifton Hill, or at least make a wax version of it....
From what I have seen it is a carbon fibre tube 5" thick. CEO refused xray inspection. Ultrasound showed internal defects and he said it was thick enough so run with it. End caps were titanium (adhesive bonded). Window was rated to less than half of the dive depth (but that was an externally engineered product so factor of safety may have save them there).
CEO also refused to hire 50 yo white guys as they were too stodgy and not innovative enough (ie they had enough life experience to incorporate factors of safety and redundancy).
Yup. The fired guy was more worried about fatigue cracking from the cycles than the first dive. CEO said don't worry, we designed a system never before seen in the world and with no external review to make sure we are fine. Theoretically, it was supposed to listen for fibers breaking and if the pace picked up, drop the emergency weights. Sadly, at 6000 psi, the time between fibers starting to break and catastrophic failure may be really short (milliseconds according to one materials professor interviewed). Every fibre that breaks requires nearby fibres to carry additional load so they break and so on. Like undoing a zipper, takes a bit to get it going but then it's over really quickly.
Reporters were harassing coast guard about time to reach site with capable rescue equipment. Coast guard says there was not even a theoretical rescue plan in place yet alone one that was staffed, equipped and trained. They had to develop the plan and source equipment on the fly.
EDIT:
Apparently this was trip four to the titanic for this vessel. A UK sub commander said he didn't know what the inspection regime was or number of useful cycles. Like all shysters, a hand pat and "that looks good" seem to be a highly probable scenario.
I can't find any mention of epirb either. Co-founder of OceanGate said his biggest fear was the Titan had surfaced and they couldn't find it in time. F me. Absolutely zero rescue planning from these idiots. We had a multi-page thread discussing PLB's for middle class bikers and they have billionaires going to the titanic with official rescue plans limited to hopes and prayers.
They have found and recovered black boxes from depths greater than the Titanic. Hopefully Titan Mark 2 will at least include the same transponder tech.
They have found and recovered black boxes from depths greater than the Titanic. Hopefully Titan Mark 2 will at least include the same transponder tech.
I can't see oceangate surviving this. Whether there will be a copycat company that fires up (hopefully one that doesn't suck) remains to be seen. Using "research" as an exemption anytime someone disagrees with international law may finally get some action though. What's crazy is that there are existing tested and certified submersibles that can go far deeper (and have gone far deeper) than this. The whole roll your own program was just ego and money.
EDIT:
Unsurprisingly, most of the competitors that don't kill you are spheres. It's hard to fit enough paying "researchers" in a sphere according to SR.
Also, did mother ship not have passive sonar constantly recording? An implosion should have been pretty easy to detect if you were listening.
Reporters were harassing coast guard about time to reach site with capable rescue equipment. Coast guard says there was not even a theoretical rescue plan in place yet alone one that was staffed, equipped and trained. They had to develop the plan and source equipment on the fly.
This is the most mind boggling part.
The starting point of the whole endeavor should have been, what happens if it goes wrong. If you do not have an answer to that, you don't start production.
Honestly though, anyone that took even a cursory look at this thing should have noped the f*** out.
Even if you surface, but are not found in time, you die? WTF?
This is the most mind boggling part.
The starting point of the whole endeavor should have been, what happens if it goes wrong. If you do not have an answer to that, you don't start production.
Honestly though, anyone that took even a cursory look at this thing should have noped the f*** out.
Even if you surface, but are not found in time, you die? WTF?
He was like musk. All ego and bravado. Don't worry, we have computers, it is safe, trust me. It didn't even look like there was a manual release for the weights. You pressed the elevator button to drop them and ascend. No angry pixies, no elevator button. Pretty much the design guide for Autopilot and Full self-driving. Whoops, killed someone, will change that code soon. Deaths in the pursuit of the future are reasonable.
He was like musk. All ego and bravado. Don't worry, we have computers, it is safe, trust me. It didn't even look like there was a manual release for the weights. You pressed the elevator button to drop them and ascend. No angry pixies, no elevator button. Pretty much the design guide for Autopilot and Full self-driving. Whoops, killed someone, will change that code soon. Deaths in the pursuit of the future are reasonable.
I understand why there are no manual controls, you need holes in the sketchy hull in order to do that.
It should be a 'fail safe' mechanism, no pixies, deploy elevator, loss of signal, deploy elevator, smell a fart, deploy elevator....
I understand why there are no manual controls, you need holes in the sketchy hull in order to do that.
It should be a 'fail safe' mechanism, no pixies, deploy elevator, loss of signal, deploy elevator, smell a fart, deploy elevator....
You could have something like magnets to hold the drop weights. No hull penetrations required. If you are smart, the magnets will hold the release pins so they don't need to hold the entire weight.
Kevlar will just add abrasion resistance but in general it has a lower tensile strength and no difference compressive. Tensile strength of a composite comes mainly from the fibres being "pulled", like pulling a string. Compressive strength comes mainly from the epoxy being compressed as a fibre (like a string) has no strength being pushed. The matrix or layup is not all fibres in one direction of course and orientation will provide strength in multiple planes. Regardless it is a less then optimum choice for a vessel where the pressure is higher on the outside as there is lots of compression forces.
Can it work, sure. Is it the best solution to the problem, likely no. In the end it is a submarine and they had to add ballast to it so a heavier material better suited to the problem might have been a better choice??? But is all about carbon fibre these days....
I think you're looking at the characteristics of a beam vs sphere. Carbon fiber, like concrete, has excellent compression but lousy elasticity -- both are incredibly good at handling compression pressures when used to make round or spherical vessels.
Think of an egg, the shell is made from calcium carbonate about one-hundredth of an inch thick A piece of the shell would crush with the pressure of a pinky finger, but if the egg is intact and the pressures equally distributed it would stand 250ATM which means it should stay together down to 8000' below sea level.
That said, any impact changes things as the forces are no longer equally distributed. A light collision and the egg (or submarine) could explode.
That's why I wouldn't rule out the window. Take a 6000 psi pressure washer with a 20" diameter stream and fire it at that cap and momentum alone should be enough to tear everything apart.
I have a reasonable amount of experience with carbon fiber , it’s amazing stuff but failure is usually catastrophic. I use carbon tube and oval sections a lot , it has amazing compression strength in a direct path down the tube , any side load and kaboom .
@fullmetaljacket , there’s a reason ferrocement boats disappeared and are uninsured, most marinas won’t let you dock one .
This trip has so much fail attached to it , and from the sound of it , mostly avoidable . Hope they were all really well insured so the family can carry on in SanTropez. Sometimes your the shoe , some times your the ant.
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