Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Titanic tourist submersible goes missing with search under way

bbc.com

Post reply on HN
Print view View original

301–310 of 649 posts

Re: Titanic tourist submersible goes missing with search under way

#301

Post by jacquesm »

paulgb wrote: post #219
jacquesm wrote: post #209

Earlier quoted context omitted.

Then that sub should not have been designed. Because if they do surface they should be able to open the hatch.

Fair enough. I'm curious if it's uncommon on subs built for that depth, though?

Yes, very much so. There are very few of them made and most of them are ROVs not manned for very good reasons. https://en.wikipedia.org/wiki/Deep-submergence_vehicle lists about 30 of them (manned ones, there are far more ROVs), each and every one of these should be considered experimental. Typical uses are scientific exploration and navy. Tourism is definitely not a main driver behind their development.

Re: Titanic tourist submersible goes missing with search under way

#302

Post by king_magic »

engineer_22 wrote: post #48
dtagames wrote: post #26

Earlier quoted context omitted.

[flagged]

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.

> The company advertises the safety of their submersible and an active suite of sensors to detect and prevent failures.

Looks like they did a real half-assed job at exactly that.

Re: Titanic tourist submersible goes missing with search under way

#303

Post by codersfocus »

fhub wrote: post #158
homieg33 wrote: post #146

Earlier quoted context omitted.

[flagged]

As someone with a surname that is easily made fun of, I urge you to just leave off irrelevant quips.

Nomen est omen is a saying since the Roman times, and there are scientific studies that show names do have an effect on professions (eg there are more people named Art working with Art than youd statistically expect)

Re: Titanic tourist submersible goes missing with search under way

#304

Post by jacquesm »

sokoloff wrote: post #248
jacquesm wrote: post #161

Earlier quoted context omitted.

I'm sure they do. But the chances of dying on board of an experimental submarine which is subjected to absolutely insane pressures are probably quite a bit higher still than the chances of dying on K2. But whether it's higher than the Titanic exploration missions is not the same as the manned Titanic missions of which there have only been very few. Those things work right up to the moment that they do not, this stuff…

> probably quite a bit higher still than the chances of dying on K2 Across history, for every 4 people who have summitted K2, 1 person has died trying.

More Darwin award candidates then. I fully support them in their choices but I find the fascination with such endeavors hard to understand. If it is a first then I get it, that's exploration and somewhat interesting. But if it is just for kicks or bragging rights then I don't get it. To me the risks don't outweigh the benefits.

Re: Titanic tourist submersible goes missing with search under way

#305

Post by bombcar »

civilitty wrote: post #205
selimthegrim wrote: post #187

Earlier quoted context omitted.

Did they find out what it was?

> At 30,000 ft. a sharp crack rang through the ship, shaking it violently. The water pressure outside was more than 6 tons per sqare inch., and even a slight fracture in the hull would have meant certain death. It proved to be only an outer Plexiglas windowpane which had splintered under the pressure. The inner hull remained watertight. "A pretty hairy, experience," admitted Walsh. https://web.archive.org/web/2007020…

“If you hear a strange noise, remain calm. If it had been bad you would be dead before you heard it.”

Re: Titanic tourist submersible goes missing with search under way

#306

Post by sgjohnson »

xwdv wrote: post #14
beowulfey wrote: post #2

Not a lot of information about this one. Does the Coast Guard have a submersible of their own that they could use to recover, even if they were able to find them?

I’m afraid not, but other companies could be contracted. Regardless, for a sub like this to just go missing, likely means something catastrophic happened. At those pressures, the individuals likely died instantly and felt no pain.

> At those pressures, the individuals likely died instantly and felt no pain.

Only if the hull imploded. Dying from say co2 poisoning can be quite unpleasant.

Re: Titanic tourist submersible goes missing with search under way

#307

Post by jacquesm »

Lacerda69 wrote: post #204
NyxWulf wrote: post #199

Earlier quoted context omitted.

My maternal grandfather changed his last name when he turned 18, from the German Uhren to Uhrey. If your last name bothers you, fix it.

Uhren sounds fine to me, now if it was Huren i would understand

What's wrong with renting?

Re: Titanic tourist submersible goes missing with search under way

#308

Post by jacquesm »

mechhacker wrote: post #254
scarnz wrote: post #30

This appears to be the vessel in question: https://oceangate.com/our-subs/titan-submersible.html Pressure hull made from titanium and carbon fiber, capable of diving to 4000m (13,000 ft). I recall that one reason SpaceX switched from carbon fiber to stainless steel pressure vessels (fuel tanks) was the difficulty of detecting structural flaws. Can any engineers comment on whether that task is easier for a vessel expo…

I've had some work in designing vessels to take external pressure. It's fundamentally a nonlinear problem. A lot of new(and some not so new) engineers don't understand the process of solving it properly For instance, euler buckling is the simple eigenvalue problem of solving a column in compression. But, it misses: initial defect because nothing is truly straight, material nonlinear effects if the part approaches yie…

Pity this isn't a top level comment, but you're spot on. Materials science for such designs is a really hard problem. And when you start cycling them the problems get harder still.

Re: Titanic tourist submersible goes missing with search under way

#309

Post by patrec »

jacquesm wrote: post #292
patrec wrote: post #282

Earlier quoted context omitted.

In what scenario would not being sealed from the outside make a positive difference? If they managed to surface, how would being able to "get out" in the middle of the ocean be helpful? If they didn't manage to surface, under what circumstances would have opening the hatch helped?

Air.

True, although fortunately the air supply is meant to last for 4 days. As a passenger I would probably be more alarmed about the apparent absence of some kind of distress beacon than the inability to open the hatch without help.

Re: Titanic tourist submersible goes missing with search under way

#310

Post by paulpauper »

opwieurposiu wrote: post #197
carbine wrote: post #111

I'm hesitant to speculate but just sharing -- an earlier version of this submersible was scrapped: "OceanGate will take advantage of lessons learned during the construction of its carbon-hulled Titan submersible, which was originally built for Titanic journeys. Rush said tests that were conducted at the Deep Ocean Test Facility in Annapolis, Md., revealed that the Titan’s hull “showed signs of cyclic fatigue.” As a r…

The hatch is bolted shut from the outside. When you make it back to the surface, there is no way to get out without external support. If the mother ship can not find the sub the occupants could be trapped bobbing just below the surface until their air runs out.

it should be findable by simple radio/celular contact?
Post reply on HN