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In 2009, Two Nuclear Submarines Collided Under the Sea (2016)
- FridayoLeary 5y agoAnd they didn't even realise...
- uga4012 5y agoAre they really not detectable from space?
- jaywalk 5y agoWhy do you think they would be detectable from space? That doesn't make any sense.
- chinathrow 5y agoWhy do you think that no nation states and their 3 letter agiens might have developed such technology by now? We basically know nothing about what current NRO spy sats carry, or do we?
- changoplatanero 5y agoThere is a technique for finding nuclear submarines from space by using satellites to look for the hot water exhaust from the nuclear reactors.
- NovemberWhiskey 5y agoLet me get this straight - there's a technique for detecting changes in the surface temperature of the water from a submarine that's probably hundreds of meters below the surface?
- willvarfar 5y agoYes. There are also magnetic anomaly detectors (MAD) and various wake detection approaches. Do these work all always? Probably not. But they work often enough to be researched and used. https://m.youtube.com/channel/UC9bMgCQyFNaMPsK9GtzM5dQ https://m.youtube.com/channel/UC9bMgCQyFNaMPsK9GtzM5dQ is a good starting point.
- NovemberWhiskey 5y agoThat's an entire YouTube channel. Where in this mess of videos can I find a reference to thermal detection of submerged submarines, please?
- hindsightbias 5y agoClosed cycle steam generation plants aren't going to exhaust much. They can't filter seawater fast enough for use and you couldn't run seawater through those systems w/o messing them up. Wastewater is probably cooled before release.
- cryptonector 5y agoSubs must necessarily produce heat. That heat has to go into the surrounding (usually very cold) water. This is unavoidable. Those nuclear reactors are cooled with that surrounding water, though obviously through heat exchangers.
- postalrat 5y agoWouldn't cooling something with water warm up the water?
- hindsightbias 5y agoIf it sat still for hours and a shallow depth, thermodynamics is thermodynamics. Very different from the idea of passing tons of seawater through a reactor and dumping it out. It's not like a jet engine flying through the sky.
- cryptonector 5y agoThese subs are large, metallic, full of electric equipment, and heavy. They have magnetic and gravitational effects on their surroundings. They also have electromagnets to help hide their magnetic signatures. A network of very sensitive satelites with very precise clocks could be used to detect gravitational anomalies -- maybe, I'm not sure what kind of precision would be needed, or if that is achievable.
- kragen 5y agoThey're the same density as the water they're floating in, even though they contain some metal that is much denser.
- detritus 5y agoUsing what technology? I can imagine in some future there being the means, but I find it hard to believe we have that level of tech available to the sort of packages we can aloft into orbit now.
- dmos62 5y agoThey're hardly detectable from Earth.
- SonicScrub 5y agoAny detection from space would have to use an optics system to detect light bouncing off the submarine. This light could be either the naturally occurring visible light, or some form of active system (probably emitting radar waves). Unfortunately light can't penetrate very far into water, so this idea is a non-starter. Light can barely make it 200m into the ocean (meaning 100m depth for light to make a round-trip and back for detection), and subs can go as deep as 300m. Any satellite-based detection system would have to rely on catching the sub while on the surface. I'm positive this is being attempted constantly, but catching a sub at depth is an entirely different manner.
- TeMPOraL 5y agoLet's hope not - that submarines carrying nuclear weapons are undetectable is the only thing that's keeping the major powers from going to war.
- jazzyjackson 5y agonext time you're out on the open ocean check how far down into the water you can see, and then check out this graph [0] of electromagnetic radiation absorption of water: visible light is the best case scenario. there's a reason sonar is acoustic and not light based [0] http://hyperphysics.phy-astr.gsu.edu/hbase/Chemical/watabs.html http://hyperphysics.phy-astr.gsu.edu/hbase/Chemical/watabs.h...
- sca4 5y agoLot of dismissive reactions to these questions, but there actually are non sound related signals we use to detect submarines and there is absolutely research on how to do that from space. This article is great, but just read the "Signal Processing" section if you're interested in space. https://www.aspistrategist.org.au/prospects-for-game-changers-in-submarine-detection-technology/ https://www.aspistrategist.org.au/prospects-for-game-changer...
- bambax 5y agoInteresting article. Also, we are now able to reconstruct a conversation by analyzing the movement of the glass on a window to the room where people are talking. It doesn't seem absolutely out of reach that we could some day detect huge underwater vessels from analyzing surface perturbations.
- traeregan 5y ago> reconstruct a conversation by analyzing the movement of the glass on a window to the room where people are talking May I please have a link to more information? I wasn't able to find anything, and this is very interesting.
- puglr 5y ago"reconstruct conversation glass vibration" brings up a lot of relevant results from a 2014 story from MIT. Sounds like it works in principle with any medium that can have its visible vibrations monitored (bag of chips is the main example, but they talk about other options such as plants or a glass of water).
- bambax 5y agoYes I think that's what I was referring to; I may have confused glass and chips but it seems it works with either medium. https://news.mit.edu/2014/algorithm-recovers-speech-from-vibrations-0804 https://news.mit.edu/2014/algorithm-recovers-speech-from-vib...
- nradov 5y agoThe US Navy has researched the possibility of detecting shallow submarines from space since at least the 1990s by looking for subtle wake turbulence on the surface. The results are classified so we don't know if they were ever successful. It's not completely impossible, but the signal to noise ratio would be extremely low.
- skinkestek 5y agoI won't say modern submarines can or cannot be detected from space, but this should give you some ideas about what is publicly known: https://duckduckgo.com/?q=spotting%20submarines%20using%20magnetic%20fields%20&t=fpas https://duckduckgo.com/?q=spotting%20submarines%20using%20ma... This is fairly open secrets to the degree that it is secret at all so it probably also is no big secret that passive and active countermeasures are used to prevent these techniques.
- cryptonector 5y agoThat's not a bad question. Subs would be detectable using magnetometers, except that they have electromagnets in them to hide their magnetometer footprint. Still, this is not perfect. Large subs have somewhat detectable gravitometric footprints that could be observed from space, indeed.
- lnwlebjel 5y agoNot sure if they are, but I do know that the US Navy funded a lot of oceanographic research into predicting and understanding bioluminescence of marine organisms for this very reason. The surface waters of the North Atlantic have massive spring blooms of phytoplankton, which are sometimes bioluminescent, and could certainly give away the presence of a large subsurface vessel, possibly from space.
- baobabKoodaa 5y agoSo the submarines can't use active sonar, because their number one priority is to avoid detection... but then these subs are all parked in the same "parking spots" in the ocean. If the favored parking spots for submarines are so rare and small that collisions happen more than once, surely that undermines their stated number one priority of remaining hidden? If someone wanted to locate enemy submarines, surely they could just send a bunch of underwater drones to swim through these parking spots?
- wil421 5y agoYou don’t need drones. Planes and helicopters already drop sonar buoys for the exact reason you stated. A better solution would be for an escort when they get into crowded lanes. Surface ships can use active sonar to scan for other subs while being some what close to their sub. The only problem is other listeners can pick up on what is reflecting off your active sonar as well. Also the subs try to avoid ever being detected because they can save your signature for comparison later.
- nradov 5y agoIt's not like any navy has spare surface warships with active sonar available to escort submarines through constricted navigational channels. There are also environmental concerns with active sonar due to impacts on marine life, especially cetaceans. During peacetime it's usually only allowed in designated exercise areas.
- wil421 5y agoI have sonar on my kayak. You can certainly use a power that is not going to hurt sea creatures. A lot of Navy ships including submarines have off the shelf sonar as well as military sonar. I’ve seen a pic of a sub with Raymarine radar they use when surfaced in channels. The subs don’t want to use their own military grade stuff because then the enemies have the frequency signature so they use off the shelf for navigating in public areas.
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- codezero 5y agoSubmerged shipping containers seem like a fantastic platform for military remote sensing.
- zoomablemind 5y agoSurprisingly, no side was assigned the blame for the collision. Unlike air traffic or surface navy accident. One had a conning tower damage, the other had a bow damage; both were supposedly slow-moving at the moment. Is there such thing as right of way for subs?
- tjohns 5y agoHow do you exercise right of way over another submarine that you don't know the position of? The whole point of submarines is that they're stealthy. Active sonor would give away their position. They're basically swimming blind. The only way this all works is the ocean is big enough that random collisions are statistically rare - but there's not much actually preventing them.
- zoomablemind 5y ago> ...They're basically swimming blind. It did appear just like that. Shouldn't there be some proximity sensors to avert collisions with massive bodies? After all in the aftermath both subs were rendered mission incapable.
- idoh 5y agoHow would the proximity sensors work? The can’t go active sonar…
- dotancohen 5y agoOptical, perhaps? How much light is at these depths? How do the subs avoid terrain?
- jvzr 5y agoI remember (barely) from a diver friend that colors disappear below 20 meters (everything appears blue, unless a bright light is shone), and sun light disappears completely below 70 meters. You'd assume that an optical system with flood lights could theoretically work, but then it would be pretty simple to monitor for light at these depths (for counter-intelligence/retaliatory purposes)
- dotancohen 5y agoEven more amazing, only a month later (or before) two satellites collided in LEO. Literally astronomical odds, and the two incidents happened so soon after one another as well.
- clipradiowallet 5y agoPie in the sky ideas here... but how far is active sonar effective for? Can you launch a probe that enables active sonar some 50-100 miles away, and radios the results back? Or would the depth prevent any type of radio communication...or is active sonar not that long-range? This whole field is really fascinating to think about.
- nradov 5y agoThe effective range of active sonar varies tremendously based on many factors: power output, microphone sensitivity, signal processing, bottom contour, water temperature, ambient noise, etc. There is no typical range. Aircraft can drop active sonobuoys but they're very expensive and in limited supply. Use of active sonar is restricted in many areas due to impact on marine life. Water blocks all radio traffic except for extremely low frequency. The bandwidth on that is too low to use as an effective navigation aid, and transmissions can only be sent from large facilities on land. Some submarines can also send up floating antennas on towed buoys but they prefer not to do so due to the risks of detection and entanglement.
- daveslash 5y agoRe >> "the French Ministry of Defense reported that the submarine had suffered a collision with an “an immersed object (probably a container).”" and Re >> "At some point, the two navies compared notes" I get that ballistic submarines want to stay secret and use passive sonar, instead of active sonar. But I also would have thought - if a submarine mysteriously ran into something under water that they did not expect to be there, that they'd start taking a more "active" approach to figuring out what was going on. It'd be like if I tried to walk blindfolded through a large & empty conference room: if I bumped into a whole wall after walking only 3 or 4 steps, I'd be very confused!
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- jjk166 5y agoIt sounds like both subs took damage around their sonar systems, so it's possible they couldn't use active sonar after the collision even if they wanted to.
- ARandomerDude 5y agoThe trouble is whom and how to ask. The submarine world is a giant, international cat and mouse game, and asking around gives away operational details that may involve compromising other things (e.g., special operations deployments) if you say "at exactly X coordinates at time T we bumped into something. Anybody know?" Also, since the dawn of militaries, much of what occurs is posturing. You want the other side to think you are big, bad, competent professionals. "We ran into something and we don't know what" makes you less superhuman in the eyes of the public and potential adversaries.
- Galxeagle 5y agoOne really fascinating aspect of sonar that leads to risks/collisions like this, is that there are ‘blind spots’ in the ocean. Because sound waves pass differently through water of different temperature and salinity and both of those change on gradients in the ocean, there are mathematical solutions to where a sub would be totally undetectable given a ship’s position and radar frequency. Because these locations are obviously useful for subs, two+ can sometimes end up in the same warm pocket, which obviously increases collision chances from a naive hundred-cubed-km search space https://m.youtube.com/watch?v=AqqaYs7LjlM https://m.youtube.com/watch?v=AqqaYs7LjlM
- archsurface 5y agoUnder the sea? What were they doing there?
- Johnny555 5y agoeach carrying 4 and 6 nuclear warheads respectively. Losing such apocalyptic firepower on the ocean floor would have been a catastrophe. However, nuclear warheads are not susceptible to “going off” as a result of a collision. What is the catastrophe if this had happened? The weapons won't explode. Is it the danger that they'll leak their radioactive fuel, or that they'll be captured by some enemy power before they can be retrieved (if they can be retrieved at all)?
- sxates 5y agoIts a little weird that the catastrophe described is about the warheads, not the loss of the whole crew. Though I'm sure it's about a billion dollar loss of hardware as well.
- egberts1 5y agoJust running off of an idea of transplanting land-based technology into underwater. One could deploy low-power laser scanning as an anti-collision mechanism when venturing into narrow channels, no?