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Titanic tourist submersible goes missing with search under way

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121–130 of 649 posts

Re: Titanic tourist submersible goes missing with search under way

#121
post #85

Skimming the website, I assume this submersible is using electromagnetically attached drop-weights so that if anything goes wrong and power is lost, the weights drop off and the submersible floats up to the surface again? And 96 hours of life support sounds good, but unless there is another submersible nearby that can dive down, find them AND attach a line, the number of hours of life support will be irrelevant. Of c…

David Pogue went down with the same vessel last year for CBS: https://www.youtube.com/watch?v=29co_Hksk6o "I couldn't help noticing how many pieces of the sub seemed... improvised."

@2:40 reading contract: “[…] an experimental submersible vessel that has not been approved or certified by any regulatory body and could result in physical injury, disability, emotional trauma, or death. Where do I sign?”

Re: Titanic tourist submersible goes missing with search under way

#123
post #95
post #82

Earlier quoted context omitted.

The CBS news article referenced in another reply says the body of the sub is 5-inch thick carbon fiber with titanium used in the rounded ends. I am surprised it’s just carbon fiber in the body.

Here is an article with a few more details on the construction of the Cyclops vessel: https://www.compositesworld.com/articles/composite-submersib... ...still not seeing what the carbon fiber is buying here, other than historical reasons / "that's how we do composite pressure vessels". Maybe it adds some slight rigidity when it is being raised up out of the water?

From the linked article: "OceanGate CEO Stockton Rush says the company had been evaluating the potential of using a carbon fiber composite hull since 2010, primarily because it permits creation of a pressure vessel that is naturally buoyant and, therefore, would enable OceanGate to forgo the use — and the significant expense — of syntactic foam on its exterior."

Re: Titanic tourist submersible goes missing with search under way

#124
post #121
post #85

Earlier quoted context omitted.

David Pogue went down with the same vessel last year for CBS: https://www.youtube.com/watch?v=29co_Hksk6o "I couldn't help noticing how many pieces of the sub seemed... improvised."

@2:40 reading contract: “[…] an experimental submersible vessel that has not been approved or certified by any regulatory body and could result in physical injury, disability, emotional trauma, or death. Where do I sign?”

Oh it keeps going at 3:30: [CEO gestures at interior lighting] “I got these from… Camper World.”

“We run the whole thing from this game controller.” [shows some knockoff controller]

Re: Titanic tourist submersible goes missing with search under way

#125
post #98

Earlier quoted context omitted.

That's a particularly crass thing to say about someone while their life is in jeopardy. >Did it not occur to anyone that it might be a bad idea? It's hard to be sympathetic in the face of such arrogance The company advertises the safety of their submersible and an active suite of sensors to detect and prevent failures.

https://youtu.be/29co_Hksk6o?t=157 Having been linked this elsewhere in the thread I don't quite like the fact that they're so brazen that they bought internal lighting from Camping World and drive it with a Logitech USB gamepad and using half-ass construction piping as a ballast. Or the fact that they scrubbed a Titanic launch for the media due to weather (presenting from some kind of briefing room where they presen…

I think you have unreasonable expectations. Off-the-shelf components may be more reliable than custom developed products (especially since you can afford a backup or two).

Also, with respect to emergency ballast - cheapness is a virtue. You're supposed to drop it in an emergency, and hesitating because "I don't want to lose my expensive weights" could kill you. This is a consideration for recreational scuba too, instructors recommend buying cheap weight belts (and the companies selling expensive ones usually advertise "free replacement if you use them in an emergency").

Re: Titanic tourist submersible goes missing with search under way

#126
post #98

Earlier quoted context omitted.

That's a particularly crass thing to say about someone while their life is in jeopardy. >Did it not occur to anyone that it might be a bad idea? It's hard to be sympathetic in the face of such arrogance The company advertises the safety of their submersible and an active suite of sensors to detect and prevent failures.

https://youtu.be/29co_Hksk6o?t=157 Having been linked this elsewhere in the thread I don't quite like the fact that they're so brazen that they bought internal lighting from Camping World and drive it with a Logitech USB gamepad and using half-ass construction piping as a ballast. Or the fact that they scrubbed a Titanic launch for the media due to weather (presenting from some kind of briefing room where they presen…

> drive it with a Logitech USB gamepad

As opposed to the professionals who went with a microsoft xbox controller? [1]

> Or the fact that they scrubbed a Titanic launch for the media due to weather

Yes? Weather is a thing. This is not a ride at disney land, of course they cancel the operation when the circumstances are not favorable. In fact doing the opposite would be foolish.

The company in question might be full of jokers, but your points don’t quite illistrate this well. They are about appearances and not substance.

1: https://www.theverge.com/2018/3/18/17136808/us-navy-uss-colo...

Re: Titanic tourist submersible goes missing with search under way

#127
post #124
post #121

Earlier quoted context omitted.

@2:40 reading contract: “[…] an experimental submersible vessel that has not been approved or certified by any regulatory body and could result in physical injury, disability, emotional trauma, or death. Where do I sign?”

Oh it keeps going at 3:30: [CEO gestures at interior lighting] “I got these from… Camper World.” “We run the whole thing from this game controller.” [shows some knockoff controller]

I found the (wireless, $30) game controller:

https://www.amazon.com/Logitech-Wireless-Nano-Receiver-Contr...

and this from a review:

“Pretty good controller, fits in hand comfortably and is compatible with anything I throw at it in a Debian linux environment. The conductive pads are extremely low quality though as I've had to replace them 3 times in the 2 years Ive been using it. For a Logitech product I expect better build quality and reasonably easier to find replacement parts but not true for this product.

Last night I had the left directional button go out on me and without parts on hand I ended up breaking down an old wired controller I had laying around. The IZDTech controller i used for parts is over 5 years old and the conductive pads are still in good shape. With a little modification I was able to get them to sit 'okay' on the buttons. Until i can find the appropriate conductive pads this will have to do.”

Re: Titanic tourist submersible goes missing with search under way

#128
post #22

Earlier quoted context omitted.

Maybe it's for if you want rescuing from the wreck.

" Goliath Awaits is a 1981 American made-for-television action adventure science fiction thriller... about an ocean liner sunk by a German U-boat in 1939 whose wreck is discovered in 1981, with over 300 survivors and their descendants living in an air bubble inside the ship."[1] Watched it as a kid, and it definitely stuck in my head. Quite impressive cast. 1. https://en.wikipedia.org/wiki/Goliath_Awaits

And the movie is in the public domain, so you can stream it on the the internet archive!

https://archive.org/details/goliathawaits1981

Re: Titanic tourist submersible goes missing with search under way

#129
post #65
post #62

Earlier quoted context omitted.

Wouldn't the sub have a tether to the surface, or is that not practical for some reason?

~2.5 miles of tether might be an obstacle.

That's how you bring several kW of power down to an ROV.

An umbilical cable, copper conductors and fiber optics inside steel wire sheath. The weight of the thing makes it impossible to attach it directly to the ROV - It would be unmaneuverable - so instead they bring it down to a TMS (Tether Management System) - basically a cage where the steel umbilical terminates and a spool of lightweight tether cable, 100m or so, which the crew then pays out to give the ROV the capability to snoop around at depth.

Re: Titanic tourist submersible goes missing with search under way

#130
post #73

Earlier quoted context omitted.

I'm not sure there's any particular reason to think that this is an extraordinarily dangerous activity relative to things like mountain climbing--even on many less extreme peaks.

I don't see any reason to think why it isn't. Unless you don't have a basic understanding about the most primitive laws of physics. Even the slightest mishap at that depth and you're in more trouble than you would be if you were stranded on the ISS.

Some mountains like K2 have an extremely high kill rate and it still happens almost every year. Probably higher killing rate than all the Titanic exploration missions that did not explode in the past. It's not so much about physics but just looking at probability
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