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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
by ralphhughes 3y ago
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 course if the pressure hull has failed catastrophically it will have been over mercifully quickly. Anyone know if deep-diving submersibles are required to carry black-boxes like aircraft?
- gexla 3y agoSome articles I found suggest that a trip was 8 hours to get there and back. Another mentioned being in the sub for 12 hours. I'm guessing it's a 4 hour trip each way and then they spend a number of hours checking the wreckage. The wreckage site is around 370 miles from Newfoundland, Canada. Seems like the rescue effort could be unfolding over days.
- imglorp 3y agoA location pinger would be a no brainer but like you say, it only helps if there's another sub with a grapple in range, in time. I understand why oceanographers /might/ want to do this, but not in person when ROV tech is so good now, for biology and tourism. There are so many things that can happen to fragile humans in that complex machine: drowning, freezing, asphyxiating, crushing, oxygen narcosis, nitrogen narcosis, co2 poisoning, and the plain old bends. So why do people risk all that, and pay 125k to do it? Why the titanic obsession? It's only the fourth worst maritime disaster (Doña Paz in 1987 had 4k deaths) and so what if someone made a movie about one.
- HeyLaughingBoy 3y agoPeople do all sorts of risky things. We're human.
- swader999 3y agoTrust in experts.
- mannykannot 3y agoNot that it appeals to me, but I would guess that the appeal of the Titanic lies in it being the canonical 'technological hubris' story and a contender in the 'if only...' category.
- ryanfreeborn 3y agoAnd the fact that it sank on its maiden voyage. The tragic irony makes it obvious why humans bestow such significance upon it.
- nickmcc 3y ago“I cannot conceive of any vital disaster happening to this vessel,” said Captain Edward Smith, commander of the Titanic.
- sacrosancty 3y ago[dead]
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- belorn 3y agoIt is one thing to do it in person and an other to see it on a screen. As a diver I can fully understand why they want to go down there, for the same reason astronauts want to visit space instead of just sending up a satellite with a video camera. That said, yes, titanic might not have been my choice personally. It has a sister ship that lies at a more reasonable depth of ~100 meters, so divers can actually be in the water and explore the inside. It is also fairly intact in contrast to titanic which is broken in half with the stern being mostly destroyed.
- sgjohnson 3y ago> So why do people risk all that, and pay 125k to do it? People enjoy casual risk-taking. If I had the 125k to dish out for this experience, I probably would have done so myself.
- jacquesm 3y agoLucky you, then.
- asylteltine 3y ago[dead]
- jiveturkey 3y ago> mercilessly quickly mercifully quickly?
- sixQuarks 3y agoHuge implosion at very high pressure. Would happen in milliseconds
- jonathankoren 3y agoReminds me of the story of the first crewed submersible to the bottom of the Mariana Trench. During the descent there was a loud boom, like some something massive broke. After recovering from the shock, they decided to continue the dive, because if it was something important, they would have already been dead.
- selimthegrim 3y agoDid they find out what it was?
- civilitty 3y ago> 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/20070202144233/http://bjsonline.com/watches/articles/0022_3.shtml https://web.archive.org/web/20070202144233/http://bjsonline....
- bombcar 3y ago“If you hear a strange noise, remain calm. If it had been bad you would be dead before you heard it.”
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- rwmj 3y agoWouldn't the sub have a tether to the surface, or is that not practical for some reason?
- floxy 3y ago~2.5 miles of tether might be an obstacle.
- lb1lf 3y agoThat'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.
- malshe 3y agoThis is great info! Can you please point me to any write up that explains this in more details?
- jacquesm 3y agoThere are several companies specializing in deep see ROV applications, it's a super interesting field. https://en.wikipedia.org/wiki/Remotely_operated_underwater_vehicle https://en.wikipedia.org/wiki/Remotely_operated_underwater_v... Is a great starting spot, read it and then branch out following the sources links.
- lb1lf 3y agoI went to sleep, time zones being what they are, but see that user jacquesm posted a link to a most impressive rabbit hole of engineering porn. As an aside, one of the first field jobs I attended after graduating was commissioning some equipment fitted onto the R/V Knorr, the very ship which was used for finding the Titanic. For a Titanic buff, that was a great experience - doubly so when the project manager at the Woods Hole end found out that I had more than a passing interest in the wreck, and during lunch one day suggested we go see if we could find Bob, as he believed him to be on the premises. Bob, of course, turned out to be Robert Ballard, who turned out to be an incredibly gentle and patient guy who answered each and every question I had like it was the first time he had it posed to him, despite probably having had them thousands of times before...
- lode 3y agoDavid Pogue went down with the same vessel last year for CBS: https://www.youtube.com/watch?v=29co_Hksk6o https://www.youtube.com/watch?v=29co_Hksk6o "I couldn't help noticing how many pieces of the sub seemed... improvised."
- jbverschoor 3y agoMove fast and break things Fix it in post Save/load game
- svnt 3y ago@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?”
- svnt 3y agoOh 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]
- svnt 3y agoI found the (wireless, $30) game controller: https://www.amazon.com/Logitech-Wireless-Nano-Receiver-Controller-Vibration/dp/B0041RR0TW 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.”
- spokeroni 3y ago> I assume this submersible is using electromagnetically attached drop-weights so that if anything goes wrong and power is lost I don't think they have any "drop-weights" which would make them positively buoyant. If I'm reading the spec-sheet correctly, the submersible itself weights ~1500lbs. Subs have ballast tanks which they pump with air and force out water to make themselves positively buoyant. But if something goes wrong with the mechanism to fill the ballast tanks, I'm guessing they'd just be stuck at depth. (disclaimer, I am far from an expert at this - I just have a cursory understanding of Boyle's law) edit: upon viewing this video https://www.youtube.com/watch?v=29co_Hksk6o&t=157s https://www.youtube.com/watch?v=29co_Hksk6o&t=157s they seem to have construction pipes as ballasts that they can drop :| God help the poor souls on that sub
- moffkalast 3y agoThere are typically compressed air cylinders that can expel the water in case of emergency. At least on military submarines that go down to 300m, it may not work 4km down where the pressure is ridiculous. https://en.wikipedia.org/wiki/Emergency_main_ballast_tank_blow https://en.wikipedia.org/wiki/Emergency_main_ballast_tank_bl...
- fastball 3y agoYep, I believe it would be almost impossible to have air tanks that are pressurized enough to blow out water from ballast tanks at that depth.
- manarth 3y agoStandard scuba cylinders are typically pressurised to around 230 bar, with a small proportion taking 300 bar as their standard working pressure (with margin for over-pressure). It's not too much of a leap from there to the 380 bar pressure at Titanic's depth.
- fastball 3y agoIndeed, this company[1] seems to sell COPV's that are rated for 414 bar, so my assumptions were wrong in this case. As such, I will revise my theory, and posit that the actual issue with this strategy at Titanic depths is keeping the water out of the ballast tanks once you've evacuated them. This seems plausible given that the hatch must be bolted on from the outside. If they had a method to keep 382 bar of water dynamically out of the ballast tanks, presumably they could use that same method to have a hatch that can be opened without manual screwing. [1] https://steelheadcomposites.com/composite-pressure-vessels/ https://steelheadcomposites.com/composite-pressure-vessels/
- ridgeguy 3y agoI've read that many military submarines have an "I've sunk" buoy. It detaches from the boat under commanded deployment, after some elapsed time without reset, or when external pressure rises way beyond crush depth. They're positively buoyant. They have radio beacons to report the event when they rise to the surface. edit: No cites, sorry.
- detaro 3y agohttps://en.wikipedia.org/wiki/Rescue_buoy_(submarine) https://en.wikipedia.org/wiki/Rescue_buoy_(submarine)
- neerd 3y ago> As it may be difficult to manually release the buoy, or the compartment where the buoy controls are located may have been flooded, the buoys were arranged with automatic releases, in the event of a fire or internal flooding. Such automatic sensors proved unreliable and buoys were sometimes released unexpectedly. Accidental release of a buoy would have been a hazard during wartime operations, or even during exercises. There is some indication that unreliable buoys were welded into place. This may have been a factor in incidents such as the Kursk sinking, where the buoy was not released and it was difficult to locate the wreck. I see so many parallels to bad devops patterns I’ve seen. You build your incident response protocols around a metric alarm (bouy being released). However the alarm is noisy so people either ignore the alarm or suppress it (welding the bouy in place). And then when an actual accident occurs your response is ineffective.
- marricks 3y ago> And then when an actual accident occurs your response is ineffective. Nothing can be actual human care and attention. Everything can break and no automated system made by careful people is exempt from needing that. I'm reminded that late into development of a Pixar movie servers crashed, work was lost, and the automated back up system failed. The only thing which saved it was that an artist took a copy of the project home to work on it.
- deleted 3y ago[deleted]
- spoonfeeder006 3y agoYou're saying that after the sub drops the weights it won't break the surface? If so how do you know that?
- Mistletoe 3y agoThe article says even if it floats to the surface they can’t get out. :( It’s bolted from the outside.