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Why is it more likely that it immediately imploded rather than after a few days? The latter is more probable to me as it has never been tested under water for

• WillPostForFood 3y ago
  It unexpectedly lost communications about 2 hours into its decent. That is a possible/probable point in time where something went wrong.
  • jamiek88 3y ago
    It’s also the point where they pass the depth that the porthole was rated for. They got lucky with that until they didn’t. They even fired a guy for whistle blowing about the porthole.
    • hef19898 3y ago
      Are you telling me, that the porthole of a DSV, intended to dive to the Titanic, was EDIT: not: rated for the depth the Titanic is at? This whole operation is getting sketchier by the minute...
      • inferiorhuman 3y ago
        They didn't want to spend the money to build a portal rated to 4000m.
      • inferiorhuman 3y ago
        https://techcrunch.com/2023/06/20/a-whistleblower-raised-safety-concerns-about-oceangates-submersible-in-2018-then-he-was-fired/ https://techcrunch.com/2023/06/20/a-whistleblower-raised-saf... The filing states that OceanGate refused to pay for the manufacturer to build a viewport that would meet the Titan’s intended depth of 4,000 meters. The Titanic lies about 3,800 meters below the surface. The filing also claims that hazardous flammable materials were being used within the submersible.
      • jamiek88 3y ago
        If you mean wasn’t rated then yes. It’s a shitshow from start to finish.
• EA-3167 3y ago
  "It imploded right away" explains everything. "It imploded later" requires at least two failures, first of power/comms, and THEN of the structure itself. Occam's Razor
  • pwthornton 3y ago
    And in this case, the sub had systems for resurfacing even if power was lost (including automatically after a set amount of time). It's highly improbable that it was astray for days before it imploded. The only way this could have happened is if it somehow got stuck on part of the Titanic wreckage and was unable to free itself.
  • adventured 3y ago
    Your occam is incorrectly structured. Power/comms is irrelevant to the equation in question, imploding, and doesn't add. It imploded later requires only one failure (the structural failure), just as the relatively short time duration option requires only one failure. Right away is also a later event. We have no way of knowing what its structural true condition was in terms of whether it was more likely to make it a very short duration or something more like a day.
    • EA-3167 3y ago
      As others have pointed out, there were multiple, redundant failsafes on the ballasts which would have led an intact sub to surface even if the crew were incapacitated or dead.
    • aqme28 3y ago
      You're completely ignoring that the comms went out. All we know is that comms went out early, and debris was found later. What single failure would cause both of those pieces of evidence?
      • oefnak 3y ago
        You're right, I think, but we also know that several ships heard sounds after the communication loss. You'd also need to account for that with your theory.
• danso 3y ago
  There's little other explanation for why contact would be abruptly lost. The company said that the sub has multiple forms of ballast, including systems that could be activated manually, and ties that were designed to dissolve after 20+ hours in seawater, allowing the sub to rise even if the crew were unconscious. > The latter is more probable to me as it has never been tested under water for more than a few hours at a stretch. That's not true, they've successfully reached the Titanic several times over a dozen or so expeditions. Mike Reiss (a famous writer for The Simpsons) said his trip reached the Titanic but got lost for most of the ~8 hour trip, but that another group on his trip had several hours to explore the Titanic. https://www.bbc.com/news/world-us-canada-65957709 https://www.bbc.com/news/world-us-canada-65957709 https://unsungscience.com/news/back-to-titanic-part-2/ https://unsungscience.com/news/back-to-titanic-part-2/
  • tomjakubowski 3y ago
    > The company said that the sub has multiple forms of ballast, including systems that could be activated manually, and ties that were designed to dissolve after 20+ hours in seawater, allowing the sub to rise even if the crew were unconscious. is there more information on these dissolvable ties? or their redundant ballast systems?
    • danso 3y ago
      From David Pogue's report on his trip in 2022: https://unsungscience.com/news/back-to-titanic-part-1/ https://unsungscience.com/news/back-to-titanic-part-1/ Excerpt from the transcript: But what if the hydraulic system breaks? Well, then they have roll weights. KYLE: Ah, so, we’ve got these weights here on the side, these are roll weights, we can actually roll the sub and those come off, and that gains us some buoyancy to come back to the surface. These are pipes that sit on a shelf that juts out from either side of the sub, held in place only by gravity. If everyone inside the sub shifts their weight to one side, the sub tips enough to let these pipes roll off. If that doesn’t work, there are ballast bags, full of metal shot, hanging below the sub. KYLE: These bags down below, we drop those off using motors and electric fingers. OK. But what if the electronics go out, and the hydraulics fail, and everyone inside has passed out unconscious? KYLE: There’s fusible links within these that actually can dissolve and come back in time if it’s drop off. Fusible links are self-dissolving bonds. After 16 hours in seawater, those bonds disintegrate, the weight bags drop off automatically, and you go back to the surface.
• dehrmann 3y ago
  > Why is it more likely that it immediately imploded rather than after a few days? That would mean it had two mostly independent failures (which is less likely than one).
• carlosdp 3y ago
  The sub had 7 redundant ways to surface (drop weights / ballast), several of which work without power, and one of which triggers automatically after ~20 hrs of exposure to seawater. The only way it wouldn't have already surfaced on day 1 is if it got stuck on something (and lost power, unlikely), or it imploded.
  • moneywoes 3y ago
    What I don’t get is what factors could have caused it to implode now when it didn’t previously?
    • floxy 3y ago
      Fatigue failure: https://community.sw.siemens.com/s/article/what-is-a-sn-curve https://community.sw.siemens.com/s/article/what-is-a-sn-curv...
    • dboreham 3y ago
      Material failure after a certain number of stress cycles.
      • jandrese 3y ago
        Failure modes for advanced composites are less well understood than for traditional metals as well. The sub's pressure hull was also made out of three disparate materials joined together which adds additional complications. Carbon Fiber in particular is notorious for performing flawlessly until it catastrophically fails in an instant.
    • chasd00 3y ago
      I know doing amateur rocketry pressure vessels work until they don't. Motor cases will gladly handle multiple launches and then on the 20th launch, explode. I think it's a matter of the metal fatiguing over time but I'm not sure how you measure the rate or severity.
• elp 3y ago
  If the stories about some parts only being certified to 1.3km instead of 4km are true then it was probably operating closer to the yield point than ideal. My guess is that metal fatigue started to become an issue and it failed too quickly for anyone to react. If the were too cheap to design and build it properly then they were too cheap to check for wear and tear properly.
  • j-a-a-p 3y ago
    Fatigue occurs after oscillating stress levels (far) below the strength of the material. So - stuff will break under low stress, if you apply it often enough. It must oscillate, otherwise it will never break. Some material, like aluminium, have very low minimum thresholds. A sub is subjected to static stress mostly. Quite a lot actually at these depths. And having it certified for 1.3 km hints to over stressing.
• mustacheemperor 3y ago
  If the sub imploded after the search had begun, would the search vessels have detected the sound?
  • 0x0203 3y ago
    The USCG admiral coordinating the search effort and doing all the press briefs said that yes, they most likely would have heard it if it happened after they got the listening buoys in the water.
• cpleppert 3y ago
  Immediate implosion if a far more likely explanation because give that we knew it imploded the most likely time would be immediately after the pressure vessel reached maximum or near maximum stress and it failed. The time actually is not the biggest factor; it is the number of cycles the pressure vessel has endured. An implosion after a relatively low number of cycles is consistent with past incidents with pressurization failures. As was pointed out, the submersible is pretty large and its a essentially a large cylinder which induces stress in the middle. Usually you make deep sea submersibles out of a sphere or spheroid because you don't have this failure modes. It isn't surprising it failed. They were strong claims that the company did do enough test, rejected safety advice and even had the CEO claim that at one point the titan wouldn't be able to reach the titanic because it (a model maybe?) had experience a pressurization failure. To say nothing of the materials they were using. Just comically bizarre that anyone involved in the project thought it would somehow survive let alone be safe.
  • ak_111 3y ago
    The most puzzling aspect, from what I understand from the experts, if it imploded at time and depth you are suggesting it would have been very likely to be registered by at least the controlling ship due to the noise. As you highlighted the sub is pretty large, imploding in a millisecond causes huge effects in the surroundings. So saying it got lost and imploded after a few days solves two problems. Explains why there was no implosion noise originally, and that the banging heard afterwards was the implosion. Also it has a history of losing contact in its previous tours.
    • spuz 3y ago
      > Explains why there was no implosion noise originally, We don't know that. There's a chance a noise was recorded but it wasn't made public in order not to compromise rescue attempts.
      • kergonath 3y ago
        It turns out that it’s exactly what happened.
• japhyr 3y ago
  > Why is it more likely that it immediately imploded rather than after a few days? Weren't there a lot of boats and other resources listening once it was reported missing? It's one thing for the tender to not hear an implosion when no one else was following this excursion. It seems harder to explain no one hearing an implosion when a growing number of resources were trying to detect any signs of activity from the sub.