[HN Gopher] Underwater ears everywhere
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Underwater ears everywhere
Author : lonk11
Score : 114 points
Date : 2023-07-16 19:44 UTC (3 hours ago)
(HTM) web link (computer.rip)
(TXT) w3m dump (computer.rip)
| saqadri wrote:
| Amazing read, convincingly explains a lot of confusion around the
| aftermath of the search operation. And kind of mind blowing that
| IUSS exists primarily to detect submarine movements around the
| world.
|
| I would love to learn more about the technology -- are these
| wireless transmitters? Undersea cables all around the oceans of
| the world?
| jcrawfordor wrote:
| Historically the hydrophones were attached to cables that were
| laid using AT&T cable-laying vessels, so technology extremely
| similar to the transoceanic cables of the time (thus AT&T's
| involvement). The change to IUSS added the ability of mobile
| sensors to report into this system, so there's apparently
| something available there (I would assume satellite). We also
| know that the Navy possesses buoys that trail hydrophones, and
| I would assume these can be integrated into IUSS as well. The
| modern details get to be classified though.
|
| As I understand it most of the original SOSUS arrays are still
| in operation, but I think they're more useful for scientific
| research than submarine surveillance at this point just because
| the newer arrays are much more sensitive. The locations of the
| original SOSUS arrays aren't totally public but you can put
| together some pretty good inferences about a lot of them, for
| example based on the NAVFACs that had similar cover stories and
| then closed at around the same time. Each one would have been
| the landing station and control point for a '60s array.
| samwillis wrote:
| On this:
|
| > _Instead, the battle of submarine silence has mostly revolved
| around obscure technical problems of fluid dynamics, since one of
| the loudest noises made by submarines is the cavitation around
| the screw. I don 't know if this is true today, but at least
| years ago the low-noise design of the screw on modern US
| submarines was classified, and so the screw was covered by a
| sheath whenever a submarine was out of the water._
|
| I wander if they are Toroidal or "tipless" propellers? They
| create less turbulence and cavitation.
|
| https://en.m.wikipedia.org/wiki/Toroidal_propeller
|
| Previous posts on HN:
|
| > Toroidal propellers turn your drones and boats into noiseless
| machines
|
| https://news.ycombinator.com/item?id=34571282
|
| > Sharrow MX-1: Tipless propeller
|
| https://news.ycombinator.com/item?id=33949895
| [deleted]
| maxbond wrote:
| Somewhat tangentially, I've been wondering why the Soviets
| weren't able to locate K-129. From what I've read, they searched
| in a location hundreds of miles away from where SOSUS detected an
| implosion - why didn't the Soviets pick it up? Surely they had a
| hydrophone array?
| jcrawfordor wrote:
| Well, one answer is that US hydrophone technology was probably
| superior at the time - but that's not necessarily a well-
| established fact, mostly an assumption. Still, it would stand
| to reason. SOSUS benefited greatly from cutting-edge research
| into acoustics that Bell Labs had been performing for other
| reasons, the Soviet Union probably didn't have the hydrophone
| technology or the undersea cable technology it relied on.
|
| There's a more interesting answer if you want one, although
| this is decidedly a conspiracy theory with, I would say,
| "medium" credibility within the realm of conspiracy theories.
| Some believe that both K-129 and Scorpion were sunk by enemy
| action, K-129 having been sunk by an accidental collision with
| the Swordfish and Scorpion having then been torpedoed in
| retaliation. The story goes that the admiralty of both
| countries, agreeing this situation could rapidly escalate into
| an undesirable war, agreed to suppress information on the cause
| of both incidents. The Soviet search for K-129 and American
| search for Scorpion could both have been cover operations.
|
| Yeah, it doesn't make total sense, and the evidence supporting
| this theory is a combination of circumstantial and
| recollections of people in their 80s. Besides, in the later
| sinking of the Kursk, Russian leadership immediately blamed a
| collision with a US submarine. But obviously the Russian
| political climate of 2000 was very different from 1968. It's a
| fun conspiracy theory.
|
| A more interesting conspiracy theory is that K-129 was on a
| rogue mission to launch nuclear weapons on the US and was
| torpedoed by the US (once again perhaps by Swordfish, it was in
| the right place at the time) to prevent this after being tipped
| off by by the USSR. If that sounds a bit like the plot of _The
| Hunt for Red October,_ well, it does. The evidence for this
| story is not nonexistent but it 's pretty limited, and no one
| takes it very seriously.
|
| Still, it gets at one of the oddities of K-129: the Soviet
| Union searched for it in its assigned patrol area, but the
| wreck was ultimately found far away from its assigned patrol
| area. I don't think anyone has a really good explanation for
| this. It was not at all typical for Soviet submarines to go off
| on their own, Moscow kept very tight control of them. So it
| seems that either Moscow didn't know where K-129 was (perhaps
| suggesting some kind of plot, whether of defection or rogue
| attack who knows), _or_ they knew where it was and searched
| elsewhere to avoid showing their hand (suggesting K-129 was on
| some sort of very secret mission). I tend to suspect the latter
| is more likely, K-129 may have been ordered to leave its patrol
| area and approach the US as a show of force (this happened at
| other points in the Cold War) and when it was lost the search
| was conducted in the normal patrol area to avoid revealing that
| had happened. All indications are that SOSUS was successfully
| kept secret from the USSR for quite some time, although
| certainly not all the way until 1991.
|
| Tom Clancy seems to have based The Hunt for Red October at
| least in part on rumors about K-129. Yeah, I watched too many
| submarine movies and read too many submarine books as a kid.
| What can I say, I had a middle-aged father.
| maxbond wrote:
| Gotcha. Thank you for the detailed response.
|
| I think maybe I'm underestimating the complexity of the
| technology. It seems like it shouldn't be that hard, I'm
| kinda imagining something like a weather station or a
| seismometer. But one thing you've helped me realize is that,
| at minimum, that comparison fails to account for the
| complexities of operating in a marine environment.
|
| And the undersea cables operative to passive sonar? Or are
| they more to prevent the stations from being identified and
| their signals intercepted, as would be the case of if it were
| over radio?
|
| > The wreck was ultimately found far away from its assigned
| patrol area
|
| Maybe I'm just naive to submarine stuff, I know very little,
| but this doesn't seem that weird to me. If everyone died
| onboard from, say, a fire, the vessel might keep steaming for
| a long time. Presumably, the CIA has a good idea if that's
| the case, for all the good that does us.
| jcrawfordor wrote:
| I think one of the big challenges at the time was how to
| install the hydrophones, although as I recall there was
| also a novel type of hydrophone being used. AT&T had
| invested a lot of effort into figuring out how to not only
| build long cables that would survive in undersea
| conditions, but also deliver power on those cables to
| active equipment (repeaters in the case of undersea
| telephone cables, hydrophones in the case of SOSUS). This
| involved putting several-kV (I think into the tens of kV on
| long cables) DC onto elements of the cable, and it was hard
| to design a cable that was reasonable to lay but could take
| that potential without dielectric breakdown. Remember this
| was in an era where paper was still a popular insulating
| material on communications cables, if not lead. DC had to
| be used instead of AC because on these extremely long
| cables the capacitance between the two current-carrying
| elements would end up eating up most of the power you put
| into it.
|
| Between Bell Labs and Western Electric, AT&T had a lot of
| practical expertise in designing and manufacturing some
| really complex cable bundles with high voltage and
| sensitive communications pairs nearby. This pretty much all
| became obsolete as soon as fiber started taking over in the
| '80s, but it was pretty incredible how many coaxial pairs
| AT&T was cramming into a buried cable (along with power for
| all the en route equipment!) in the '70s. Hell, AT&T
| famously held off on fiber for years because they had a
| plan to bury long microwave waveguides like cables!
| doubledad222 wrote:
| > this writing is so clear and good > Today, IUSS automatically
| detects and classifies both submarines and wales.
|
| Do the British know ?
| jcrawfordor wrote:
| I am proud to say I noticed that one about two minutes before I
| saw your comment. It's not that I _never_ copy edit, I just
| usually don 't do it until two days later.
| [deleted]
| Vecr wrote:
| I really think SAR should be realistic about what's going on and
| quickly publish what they are trying. Otherwise you can get
| people who could help showing up with the wrong equipment, or not
| showing up at all, or people showing up who think they can help
| but can't and don't know it due to the lack of information.
| jcrawfordor wrote:
| Search and rescue authorities very much do not want people just
| showing up with equipment based on what they heard on the news
| ---if you are involved in search and rescue, disaster response,
| or related areas, one of the first things drilled into you is
| that you must never "self-activate." It puts an enormous
| workload on the people in charge of the incident if you expect
| them to keep the entire world informed about the state of the
| search, and an even bigger workload if people start showing up
| without having been asked. Organizations like the Coast Guard
| have a public information function to manage the press and cold
| contacts, and a logistics function to call upon resources.
| Volunteered resources are rarely useful if they have not been
| vetted and had operational procedures established in advance.
|
| My experience is only in wildfire and structure fire, but
| everything I've heard is that the situation is much the same in
| SAR and I can only imagine the issues with needing to having
| resources prepared in advanced are only more significant at sea
| where integration is very complex.
| schoen wrote:
| How does this interact with the norm of commercial vessels
| responding to distress calls at sea?
|
| I know distress calls aren't at all the same as search and
| rescue, but in some incidents both phases must occur.
| fredoralive wrote:
| There's a bit of a difference between a ship already at sea
| altering it's course to get near and assist a vessel in
| distress (where they might be first on he scene), vs ship
| going to sea especially for an event I guess? You don't
| want the area too crowded with "good Samaritans" who've all
| gone to sea just to assist.
|
| I recall some comments saying that operators of a
| submersible that could hypothetically rescue a sub stranded
| on the bottom being discouraged from deploying for the
| Titan by the coast guard, which perhaps means they already
| knew the fate of the vessel. Although it could be that they
| already had a suitable submersible arranged already and
| didn't want more in the area causing complications with
| coordination etc.
| jcrawfordor wrote:
| Ships nearby responding to a distress call is a matter of
| expedience rather than good planning - something is better
| than nothing. But typically once an organization like a
| coast guard gets involved, they start giving orders to
| other responding ships, including sending ships away if
| they aren't needed and adding to the fray. This general
| concept is called incident command or the incident command
| system (ICS) after a set of practices that I think
| originated in firefighting but are now broadly taught by
| FEMA to all sorts of disaster responders. Basically that
| there needs to be someone in charge of the incident and
| there need to be standardized and controlled flows of
| information, otherwise it's very easy for the response to
| be ineffective and even dangerous because of poor
| communications, miscoordination, etc.
| grog454 wrote:
| An excellent read but one thing caught my attention:
|
| > The Navy did not withhold information on the detection for four
| days out of some concern for secrecy.
|
| I think it's more likely than not that the statement is correct,
| but what gives the author the authority to make the claim so
| definitively? The author's bio indicates he's a consultant and
| there is no indication of direct involvement in this or any other
| SAR effort.
|
| While the workings of the SOSUS and IUSS systems may be
| declassified, the deployments and capabilities (mostly range and
| computation related) of such systems most likely are not. And
| there is always the possibility that there is yet another system
| the author simply isn't aware of.
|
| IMO, it isn't negligence to value the secrecy of systems used for
| defense above some number of lives, in some situations.
| tw04 wrote:
| >While the workings of the SOSUS and IUSS systems may be
| declassified, the deployments and capabilities (mostly range
| and computation related) of such systems most likely are not.
| And there is always the possibility that there is yet another
| system the author simply isn't aware of.
|
| But they confirmed it 4 days later - which would be admitting
| to its capabilities. The entire talk track of: "they kept it
| secret because of conspiracy theory X" makes no sense when they
| didn't actually keep it secret, they simply didn't make it
| public until AFTER the team was there to search - for the
| fairly obvious reasons the author stated. Mainly it creates
| unnecessary publicity that is hurtful to the relatives of the
| folks that are at the bottom of the ocean, and political
| pressure to "not spend money on the search" which was already
| coming from some circles even without the Navy's information.
| grog454 wrote:
| And those are all valid reasons to delay release. My point is
| that they are not mutually exclusive with declassification,
| or verification that the information is OK to release
| publicly from a security standpoint. I'm not sure why secrecy
| automatically means "conspiracy theory".
| tw04 wrote:
| >I'm not sure why secrecy automatically means "conspiracy
| theory".
|
| It doesn't automatically, but literally everyone claiming
| the Navy was "hiding something" was going down the
| conspiracy theory route. I'm not talking about
| generalities, I'm talking about the specific situation in
| question which is the Titan sub.
|
| >the information is OK to release publicly from a security
| standpoint.
|
| What information are you referring to? It's already public
| that the navy has the system in question. It's already
| public that it is analyzing data realtime. Nothing about
| the system would have been compromised by publicly
| announcing they had detected an anomaly the day of the
| event vs 4 days later. The logical conclusion is that all
| of the aforementioned reasons are why they waited 4 days.
| You don't need clearance to get to the conclusion.
| jcrawfordor wrote:
| Well, the clearest source is that no one _claims_ the
| information was withheld, as far as I can tell that idea was
| just synthesized by podcasters and internet commenters. The
| Navy states, the WSJ reports (probably based on the Navy
| statement), and the Coast Guard mention that Navy intelligence
| reported the possible implosion almost immediately after it was
| discovered. The only thing that didn 't happen until four days
| later was the release of that information to the public.
|
| Many aspects of IUSS are still classified, and for example we
| can assume that the actual data will never be released because
| of sensitivity of the collection system. But the news that the
| Navy detected the implosion is nothing new, it would probably
| be more surprising if the Navy didn't (I don't know that the
| sound levels associated with a vessel of this type imploding
| are well known, maybe it could be explained away as the
| implosion having somehow produced almost no acoustic
| signature). We know that in the '60s the Navy detected
| submarine implosions (admittedly of larger submarines) further
| afield, and we also know that IUSS has seen major upgrades
| including new sensor arrays since then.
| maxbond wrote:
| > As far as I can tell that idea was just synthesized by
| podcasters and internet commenters.
|
| I don't use Twitter so can't confirm, but what I've heard in
| the news is that the OceanGate lawyer tweeted some vague,
| borderline conspiratorial stuff about not getting proper
| cooperation from the Coast Guard. I think the commentary
| people you refer to then boosted and expounded upon that
| idea.
|
| ETA: Partial confirmation here
| https://nypost.com/2023/06/20/oceangate-adviser-rips-us-
| gove...
|
| The statements quoted here don't match the description "vague
| and borderline conspiratorial," but they could be
| misinterpreted that way, and maybe there were others.
| tls wrote:
| [dead]
| Emily56 wrote:
| [dead]
| darkclouds wrote:
| >Much more appealing is passive sonar, which works by listening
| for the sounds naturally created by underwater vehicles.
|
| Experts in marine biology. Reminds me of the night vision camera
| the british military were showing off on BBC Countryfile program.
| Who would have thought the military are experts in biology, but
| probably explains why the brits took off sunglasses in Iraq when
| talking to people, but the US didnt. You should see the british
| scarecrows as well!
|
| > Instead, the battle of submarine silence has mostly revolved
| around obscure technical problems of fluid dynamics, since one of
| the loudest noises made by submarines is the cavitation around
| the screw.
|
| https://en.wikipedia.org/wiki/Toroidal_propeller Difference in
| cavitation. https://youtu.be/k0yzBTTqfzs?t=436
|
| Dont know if these toroidal propellers scale up to submarine
| sizes, they keep them hidden under an large oily rag along with
| the front of the subs.
|
| > did the Navy withhold information on the detection from
| searchers out of concern for secrecy
|
| Location of sensors maybe, after all something like the titanic
| will attract treasure hunters, why wouldnt interested govt's
| deploy remote sensors to detect who is in the area? Submarines
| make it easy for crew to be kept in the dark on missions as not
| many can use the periscope or other sensors.
|
| I read somewhere once that a sensor, sonar or hydrophone, in UK
| waters could detect the sounds come from a New York harbour,
| which gives an insight into the distance sounds can travel
| underwater, but considering all the noises that can be detected,
| having sound processing abilities, a little bit better than
| something like Dolby Noise Reduction, is the key part of the
| underwater arms race.
|
| https://www.theguardian.com/environment/2023/may/15/listen-t...
|
| https://news.sky.com/story/titanic-sub-search-what-are-the-s...
| jcrawfordor wrote:
| > I read somewhere once that a sensor, sonar or hydrophone, in
| UK waters could detect the sounds come from a New York harbour,
| which gives an insight into the distance sounds can travel
| underwater, but considering all the noises that can be
| detected, having sound processing abilities, a little bit
| better than something like Dolby Noise Reduction, is the key
| part of the underwater arms race.
|
| I didn't really get into this in the article but there's a
| phenomenon called SOFAR (I think this does stand for something
| but the acronym is sort of a joke). It's basically a specific
| static water pressure (and thus depth) in which sound "ducts"
| sort of like how HF radio can duct in the ionosphere. As I
| understand it, it's not at all unreasonable for a sound in the
| SOFAR channel to go clear around the world. I know there are
| cases where hydrophones have recorded a particularly loud sound
| multiple times because of it coming "the long way around" as
| well as echo effects. Some of these sounds have been things
| like "perhaps the loudest sound ever produced" and are
| attributed to seismic phenomenon, but there are a lot of
| strange things going on in the ocean and hydrophones continue
| to provide plenty of questions for marine researchers to
| answer. And, of course, at least some of the IUSS sensors are
| very intentionally placed within the SOFAR channel to
| capitalize on this effect.
| darkclouds wrote:
| It is interesting a bit like catching the sound of a distant
| rave on the wind.
|
| https://en.wikipedia.org/wiki/SOFAR_channel
| indymike wrote:
| > I read somewhere once that a sensor, sonar or hydrophone, in
| UK waters could detect the sounds come from a New York harbour,
| which gives an insight into the distance sounds can travel
| underwater, but considering all the noises that can be
| detected, having sound processing abilities, a little bit
| better than something like Dolby Noise Reduction, is the key
| part of the underwater arms race.
|
| In a typical attack sumbarine, a substantial amount of the
| ship's volume is dedicated to acoustic sensors:
| https://media.defenceindustrydaily.com/images/SHIP_SSN_Virgi...
|
| This arms race is very old, and the state of the art even 20
| years ago is pretty impressive.
| micromacrofoot wrote:
| what's the difference with british scarecrows? eyes or
| something?
| darkclouds wrote:
| 5 eyes perhaps.
| andrelaszlo wrote:
| They take their sunglasses off when talking to people. It's
| more polite.
| tomcam wrote:
| Yeah, that comment fascinated me too. I can only say that the
| character of British scarecrows is... very different from
| those in the US, although I can't articulate one reason
| exactly why:
| https://www.google.com/search?&q=british+scarecrow&
| manzanarama wrote:
| This writing is so clear and good. I can't tell you how many NYT
| articles I read where the paragraphs feel out of order, chopped
| up and there is no consistent flow. This reads very enjoyably.
| SkyMarshal wrote:
| That kind of modern journalism is absurd. Originally the rule
| in journalism was, the first paragraph must contain who, when,
| what, where, then subsequent paragraphs fill in the details in
| either chronological or logical order.
|
| Now the first paragraph must contain an emotional human-
| interest style "hook" to rope in the reader, then bury the lede
| in some random spot in the remainder of the text, in an attempt
| to keep the reader searching for it, like a slot machine.
|
| As soon as I realize that's how something is written, I take
| that as signal it lacks the quality to stand alone and I
| discard it and move on.
| hengheng wrote:
| Condensing inflated long-form articles back to their useful
| size would be a worthwhile AI application, just like
| searchable podcast transcriptions.
| chongli wrote:
| Yeah. I can usually tell within the first couple of words if
| the article is worth reading or not. Anything that seems to
| start with a complete non-sequitur or some variant of "once
| upon a time" is an immediate back-button bounce for me!
| micromacrofoot wrote:
| writers rarely have complete control over what editors do to
| their pieces before the nyt publishes them, and in this case
| there are no middlemen muddling things up
| the-printer wrote:
| The fact that he publishes informative pieces at such a steady
| rate is remarkable as well. And the fact that he resisted to
| use the phrase "deep dive" in this particular one is indicative
| of a high level of discipline with his prose.
| EMCymatics wrote:
| I wonder what supercavitation sounds like
| kayodelycaon wrote:
| I looked it up and if the video is accurate, it sounds like
| static. About what I expected a large stream bubbles to sound
| like. (Imagine a shaken soda bottle can overflowing.)
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