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World War II Tech eLoran Deployed As GPS Backup In the UK

Posted by timothy on from the department-of-redundancy-department dept.

hypnosec (2231454) writes General Lighthouse Authorities (GLA) has announced that they have deployed a World War II technology called Long Range Navigation system, which they have named eLoran, in seven ports across Britain to serve as a backup for the existing Global Positioning System (GPS). GLA notes that modern ships have a lot of equipment that rely on Global Navigation Satellite Systems for functioning and in case of failure the consequences will be disastrous. For this reason technology that doesn't rely on the GPS was required as a backup. eLoran is a ground-based system rather than satellite-based and is designed to be used in the event of a GPS failure. The system was quite successful and post-WWII era, the system was updated and crowned a new name Loran-C. The navigation system was adopted by mariners across the globe and was used until GPS was deployed. Loran has now been renamed as eLoran because of the upgrades to the technology as well as the infrastructure. The more accurate system generates longwave radio signal, which is 1 million times more powerful than those from positioning satellites, are capable of reaching inside buildings, underground and underwater. According to GLA, eLoran and GPS are quite different from one another and hence there is no common mode of failure.

96 of 139 comments (clear)

  1. Meanwhile, in the U.S. by Solandri · · Score: 4, Interesting

    Funny how two countries can take the exact same situation and arrive at completely opposite decisions.

    1. Re:Meanwhile, in the U.S. by FooAtWFU · · Score: 3, Interesting

      Well, the US operates the GPS system itself, which is a distinct advantage in a time of worldwide military conflict.

      --
      The World Wide Web is dying. Soon, we shall have only the Internet.
    2. Re: Meanwhile, in the U.S. by Anonymous Coward · · Score: 2, Informative

      It's not only the US, Norway is also about to shut down the (old) LORAN-C system.
      "The Department of Fisheries has desided to close down
      the 4 Norwegian Loran-C stations from January 1. 2016.
      Ther reason given is that there is not many users, the GPS is the
      primary navigation system, and that the equipement in use
      are old and need expensive uppgrade." source: home.online.no/~loran-c/

    3. Re:Meanwhile, in the U.S. by AchilleTalon · · Score: 3, Interesting

      Operating yourself the GPS satellites does not prevent disruption of the GPS service due to solar storms, which I believe is the most likely case behind the UK decision to keep the eLoran system. I don't neither believe shutting down selectively the service is possible in time of war. Remember the GPS communication is one-way only for the positionning devices. The satellite receives nothing from the device.

      --
      Achille Talon
      Hop!
    4. Re:Meanwhile, in the U.S. by profplump · · Score: 1

      Another way to look at it: Non-radio navigation continues to be possible, and constitutes a practical, cheap, already-in-use backup to GPS for most ship-related uses.

      LORAN is fine and has valid uses. But it also has a cost, and taking it down doesn't meant that ships will get lost or crash into each should GPS become unavailable.

    5. Re:Meanwhile, in the U.S. by Phil+Karn · · Score: 1

      Actually, the US military has a very simple way of selectively shutting down GPS: they locally jam the L1 frequency. The satellites also transmit on a second frequency, L2, with an encrypted, high precision "P(Y)" code for which the keys are closely controlled. They have receivers that can work with just the P(Y)-code, so it doesn't matter to them if L1 is jammed.

  2. re Loran by freddieb · · Score: 3, Interesting

    I remember loran from my early ham radio days (50's and 60's). It made a hell of a noise on HF. It probably would not bother anyone any more as the hf frequencies are not utilized as they once were. Sounds like an excellent idea as the gps system is very vulnerable.

    1. Re:re Loran by coolsnowmen · · Score: 1

      Modern communications has come a long way since then; it is probably possible to contain that communication to a known band and not spill into neighboring ones. Especially because one of the few times HAM is still relevant is in local emergence communications (when cell is down / overloaded)

    2. Re:re Loran by clifwlkr · · Score: 3, Interesting

      Funny you say they are not being utilized. Last weekend the bands were jammed end to end for the world wide DX contest. On the major bands the waterfall was full end to end. I made hundreds of contacts. Earlier I did a summits on the air activation and made over 30 contacts in an hour. Never mind the digital modes. The ham bands are alive and well, Jim Olsen K7JEO

  3. Err - no. by queazocotal · · Score: 3, Insightful

    The primary risk to GPS in the UK is the USA deciding to turn it off.
    That risk doesn't apply for US shipping near the US, as if GPS was turned off - rather than severely degraded - so would the local LORAN locators.
    GPS is not going away unless someone actually presses the button.
    It's not vulnerable (theoretically) to single points of failure (ideally) as it's intended to carry on even in the event of moderate wars.

    1. Re:Err - no. by Anonymous Coward · · Score: 5, Informative

      sorry but you are wrong -
      From
      http://www.bbc.co.uk/news/science-environment-29758872
      "
      The system works using a fleet of satellites orbiting high above the Earth, but the signal they transmit is weak and can be easily interfered with.
      Other sat-nav systems - such as Galileo in Europe and Glonass in Russia - have the same vulnerabilities, says Prof David Last from the Royal Institute of Navigation.
      "A little bit of power from a jammer on the frequency used by GPS close to your receiver can deafen it, and it won't be able to hear the GPS signals," he says.
      "For example, jamming is a real issue in Korea. There have now been three occasions when the North Koreans have transmitted high-powered jamming in South Korea."
      The Sun too can knock satellite systems offline, he adds.
      "It starts to transmit radio noise during solar storms, so intense that it either makes GPS positions wobble about or causes GPS to be lost across the entire sunlit side of the Earth."
      " .....

    2. Re:Err - no. by khallow · · Score: 1

      Because doing that would never massively backfire.

    3. Re:Err - no. by Megol · · Score: 1

      Would the US care? In the right situation - nope.

    4. Re:Err - no. by AchilleTalon · · Score: 1

      Turning off the GPS signal would have consequences for USA citizen in a magnitude you can confidently discard this hypothesis. Jamming the signal in specific geographic areas using jamming signals is something else. But shutting down the service? No way.

      --
      Achille Talon
      Hop!
    5. Re:Err - no. by Charliemopps · · Score: 1

      Because doing that would never massively backfire.

      When did our government ever think beyond the next election?

    6. Re:Err - no. by leathered · · Score: 4, Interesting

      In the UK pilots often receive NOTAMs stating that the military are conducting GPS jamming trials in certain areas. From personal experience and reports from other pilots the jamming is very effective.

      --
      For all intensive porpoises your a bunch of rediculous loosers
    7. Re:Err - no. by jmac_the_man · · Score: 1, Informative

      The GPS specification is public and known 100%. In the early days of the GPS system, there was a random error introduced deliberately that could only be filtered out with a military receiver. The Federal Government stopped including the random error in the early 90s, and made it against the law for them to turn the random error back on in 2000. Modern GPS satellites don't even have the capability of transmitting the error signal.

    8. Re:Err - no. by profplump · · Score: 1

      The system can be selectively disabled to prevent use in specific geographic areas. Those areas are fairly large but not global.

      And if the decision was made to disable GPS in the US they would most assuredly turn off any local radionavigation system as well.

    9. Re: Err - no. by jd · · Score: 2

      And the government always obeys the law? Further, if the facility exists, anyone can turn the jitter back on. It's no different from what we've been saying about backdoors - once they exist, anyone can use them. There's also risks of social engineering attacks against those running satellites. And, since no software is perfect (and no radiation proofing is perfect), the satellites may spontaneously add jitter, enable encryption (with a gibberish key), or simply activate their steering jets, putting them on an incorrect and/or elliptical orbit, screwing up calculations. (ie: physical jitter)

      This is ignoring the solar storm/jamming/gamma ray burst/collision with space junk range of issues, as they're discussed elsewhere and aren't really pertinent to the jitter issue.

      --
      It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
    10. Re: Err - no. by jd · · Score: 2

      The FBI wants to ban private encryption, essentially banning eCommerce, eBanking, UNIX, foreign languages, medical implants, boolean operators...

      The mere fact that the director could state this in public and not be fired by the time he'd finished speaking is all the proof you need that Americans - and indeed any post-Babbage civilizations - are expendable in the eyes of the civil (uncouth?) service.

      Which should be no surprise. The difference in social influences, culture and thus attitude between the paranoid schizophrenic survivalists and the paranoid schizophrenic security agency staff is pretty much nil.

      --
      It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
    11. Re:Err - no. by khallow · · Score: 1

      You can always find idiots who don't think about and don't care about consequences and they occasionally end up in power. But they don't stay in power.

    12. Re: Err - no. by jmac_the_man · · Score: 1

      Further, if the facility exists, anyone can turn the jitter back on. It's no different from what we've been saying about backdoors - once they exist, anyone can use them. There's also risks of social engineering attacks against those running satellites.

      Satellites launched since 2000 (roughly half the current constellation) lack the necessary transmitters to rebroadcast the jitter, and currently slated replacement satellites will also lack that transmitter. If the federal government wanted to reintroduce the jitter, they would have to replace most of the constellation. At that point, it's pretty much no longer GPS.

    13. Re:Err - no. by nogginthenog · · Score: 1

      My phone (Nexus 4) in the UK will happily pick up GLONAS satellites so there's no problem!

  4. are you sure? by wbr1 · · Score: 2

    No common mode of failure? An EMP or nuke would beg to differ.

    --
    Silence is a state of mime.
    1. Re:are you sure? by queazocotal · · Score: 2

      The satellites are hardened.
      And 20000km away from earth.
      As are the uplinks. (well, not the latter)

    2. Re:are you sure? by rossdee · · Score: 2

      See that big ball of gas in the sky 93 million miles away, thats capable of taking out any satellite based system...

    3. Re:are you sure? by Anonymous Coward · · Score: 1

      No common mode of failure? An EMP or nuke would beg to differ.

      I'm sorry, if there's a nuke going off and you're on a cargo ship the last thing in the world you're going to worry about is getting your containers where they belong.

    4. Re:are you sure? by freddieb · · Score: 1

      If they are hardened, chaff or some other form of physical blocking would easily silence the gps system in a given area. Or..just deploy a more powerful clone system with misinformation. I am sure there are many ways to disrupt the current system.

    5. Re:are you sure? by ColdWetDog · · Score: 2

      But that's natural. Mother nature would never do that to us.

      (Sings 'kumbaya'.)

      --
      Faster! Faster! Faster would be better!
    6. Re:are you sure? by wbr1 · · Score: 1

      my point was that a localized EMP or blast would knock out the ships radios and electronics not the satellites.

      --
      Silence is a state of mime.
    7. Re:are you sure? by Charliemopps · · Score: 1

      If an EMP or Nuke went off close enough to knock out this system, the loss of computerize navigation would be the least of your concerns. I'm pretty sure ship captains would turn around and avoid England irreverent of the state of navigation.

    8. Re:are you sure? by putaro · · Score: 1

      The common failure mode would be "electronics" and any type of electronic navigation would fall under that. Furthermore, if all a ship's electronics are offline their engines are probably not functioning either.

    9. Re:are you sure? by Hognoxious · · Score: 1

      If that happened you'd probably have more important shit to worry about.

      --
      Confucius say, "Find worm in apple - bad. Find half a worm - worse."
    10. Re:are you sure? by profplump · · Score: 1

      GPS can be cryptographically authenticated, at least for authorized users. You can jam it, but you can't easily fake it, at least not against receivers that are worried about such things.

    11. Re: are you sure? by jd · · Score: 2

      That may be true in theory, but Iran succeeded in hijacking a US drone via a GPS attack. Thus, whatever authentication exists is not actually in use. The US, for reasons known only to them, hate encryption. Any encryption. By anyone. Including themselves. For much of the war in Afghanistan, drone camera signals were unencrypted and omnidirectional, leading to video footage being circulated. Slashdot covered the issue in the early days of the war.

      If the US military are too stupid to encrypt drone GPS systems and drone video feeds in an open war, they can't be trusted to do anything right.

      --
      It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
  5. good to have backups by Anonymous Coward · · Score: 2, Interesting

    In the event of a war with a major world power, GPS will be destroyed, because most of those powers have proven they can shoot satellites. If you depend too much on GPS you will be in for a rude shock when it goes away.

    1. Re:good to have backups by whizbang77045 · · Score: 1

      Boy, do I ever agree with you on that! There needs to be a backup system, preferably with distributed assets, so if the worst happens, planes and shipos can still navigate.

    2. Re:good to have backups by david_bonn · · Score: 1

      The GPS satellites are in pretty high orbits (around 20000km if memory serves). I don't know if anybody has an anti-satellite weapon that can target a satellite that high. For that matter, the WAAS satellites are in geosynchronous orbit and even harder to shoot down.

      You would also have to shoot down several GPS satellites in quick succession to produce a significant gap in coverage. Since the Chinese and Russian anti-satellite weapons are based on orbital launchers (for obvious reasons) the countries in question would have to do five or six satellite launches in a relatively short time window.

      It would probably be far, far cheaper to jam GPS signals than to shoot down the satellites.

    3. Re:good to have backups by ultranova · · Score: 1

      Every major power depends on international trade to the extent that if they're trying to take down the GPS, the world is already doomed.

      --

      Forget magic. Any technology distinguishable from divine power is insufficiently advanced.

    4. Re:good to have backups by david_bonn · · Score: 1

      I don't think either Iran or North Korea has the launch capacity to put the 1000+kg that they would need to put a nuke into orbit.

      Agreed that a nuke in LEO would play merry hell with GPS and lots of other satellites. But I can't really see North Korea or Iran being crazy or stupid enough to piss off their remaining allies (or sort-of-allies) like China or Russia. Of course, we are talking about North Korea and Iran...

  6. Pretty cool by Anonymous Coward · · Score: 5, Insightful

    This is not your old 70's LORAN system. Thanks to advances in DSP processing, eLORAN gives your position with precision comparable to GPS (10m or so). It also have data channel that's used to broadcast DGPS corrections, so it complements GPS nicely.
    Because of low frequency, signal penetrates buildings and ground (however with greatly reduced range). This may be one of the solutions for a car navigation in tunels. Even if it produces less precise position, it's always better than no position at all.

    Great contrast between UK and USA, where LORAN transmitters were demolished in the past years. When so many things dependd on GPS signals, we really need some backup system for precise timing and positioning. Not thinking about backup only means we will learn about it the hard way - and it will not be pretty.

    1. Re:Pretty cool by Anonymous Coward · · Score: 1, Interesting

      Not thinking about backup only means we will learn about it the hard way - and it will not be pretty.

      Exactly. Every major world power has plans to destroy the American GPS constellation in the event of a shooting war. If you don't plan for that, it will be that much rougher when it happens.

      Wars with minor or regional powers that can't destroy GPS, that's one thing. Wars with major powers like China or Russia who can, that's something else.

    2. Re:Pretty cool by JohnStock · · Score: 1

      We do. It's called Glasnoss and Galileo. The latter when completed will be superior to GPS

    3. Re:Pretty cool by Blaskowicz · · Score: 2

      I am waiting for the Perestroïka navigation system : )

    4. Re:Pretty cool by Anonymous Coward · · Score: 1

      Even in the 70s LORAN could give 10' accuracy.

      You just used it with hyperbolic geometry instead of in range-range mode.

      The two problems with hyperolic is that you needed at least 3 stations to get a position, range-range could get your position with two.

      For GPS, you need 4 satellites to get a 3D position (needed for flying), 3 would get you a 2D position (Ok if you know you are on the ground...)

    5. Re: Pretty cool by mtempsch · · Score: 1

      We need a solution to car navigation in tunnels? You just continue straight ahead until you emerge from the tunnel.

      There are places in the world that have intersecting tunnels...

    6. Re:Pretty cool by dabridgham · · Score: 1

      You could determine your 3D position with three satellites if you had an atomic clock. Since you don't, you need a fourth satellite to solve for four unknowns: x, y, z, and time.

    7. Re:Pretty cool by rnturn · · Score: 1

      Clock quality isn't the problem. You need four satellites even if you have an atomic clock. If you had a clock that was perfectly synchronized to GPS system time, you could get by with three SVs.

      --
      CUR ALLOC 20195.....5804M
    8. Re:Pretty cool by jabuzz · · Score: 1

      Thing is today a chip scale cesium atomic clock with inputs for synchronization to GPS is under 2000USD and the size of a box of matches. So it is perfectly possible.

    9. Re:Pretty cool by tlhIngan · · Score: 1

      This is not your old 70's LORAN system. Thanks to advances in DSP processing, eLORAN gives your position with precision comparable to GPS (10m or so). It also have data channel that's used to broadcast DGPS corrections, so it complements GPS nicely.
      Because of low frequency, signal penetrates buildings and ground (however with greatly reduced range). This may be one of the solutions for a car navigation in tunels. Even if it produces less precise position, it's always better than no position at all.

      Great contrast between UK and USA, where LORAN transmitters were demolished in the past years. When so many things dependd on GPS signals, we really need some backup system for precise timing and positioning. Not thinking about backup only means we will learn about it the hard way - and it will not be pretty.

      Depends if they only plan to deploy them along coastlines or everywhere.

      LORAN worked only because it had a collection of towers spread out in a line, and the preferred navigation route (most accurate) for LORAN involved being perpendicular to the line. For shipping routes that was great since they generally were well defined paths.

      But if you're randomly tuning in a LORAN station, the accuracy (especially "reversed") was questionable at best.

      The US decommissioned them because they were expensive to maintain, few people were using them (compared to GPS) and touchy to use.

      Plus, GPS is so integral to US life that introducing an error signal back or turning it off would literally disrupt the US economy. Not just satnav, but satellite tracking and monitoring of equipment, timing (GPS is used to distribute time and synchronize clocks (required for cellphones)), navigation (RNP - Required Navigation Performance, is a new method airplanes use to approach airports that lets them fly closer in and lowered minimums, and relies heavily on GPS, which saves time (less time cooped in the cabin) and fuel, and makes the airports more efficient). The trucking industry heavily relies on GPS to track its cargo being moved about as do many package delivery companies.

  7. Re: LMFAO by Anonymous Coward · · Score: 1

    We have lived thousands of years without electricity so a global power outage shouldn't be a problem

  8. Re:Wait wait wait by ColdWetDog · · Score: 1

    "What a retard"

    Yes, the generic Space Nutter point of view I'm lambasting is quite retarded, yes.

    So how did they have a positioning system before Sputnik?

    Loran isn't nearly as convenient as GPS. Since it's longwave (relatively low frequency radio waves) it needs longer antennas. It needs powerful ground stations within (IIRC) a thousand miles or so. It would be hard to put in your cell phone.

    The other competitor* in the 'where the heck am I' competition is solar or celestial navigation (think sextant and a nice, accurate watch). Simple tech, although I can't see teaching people in Starbucks how to use a sextant (it helps if you are outside and can see the horizon which cuts out vast swaths of humankind).

    So, life for the geographically confused was much harder pre GPS. You should try it sometime, it's interesting navigating a large boat at night using loran (or dead reckoning).

    * I'm sort of glossing over inertial navigation but the smallest iNav systems I've seen are shoebox sized and Gucci-shoe priced. Suitable for expensive large ships and submarines but Starbucks, not so much.

    --
    Faster! Faster! Faster would be better!
  9. Re:LMFAO by ColdWetDog · · Score: 3, Interesting

    in case of failure the consequences will be disastrous

    Yeah, because no shipping ever occurred before LORAN or GPS. What a joke! It's not like people found their way around the globe for centuries using the sun, moon and stars.

    Actually, we HAVEN'T been shipping super sized cargo ships without at least LORAN. The need for near continuous, weather independent localization pretty much coincided with the development of radio. We COULD develop different back up systems - for example inertial navigation systems have progressed from refrigerator sized boxes with a price tag suitable only for military ships to a shoebox sized box priced reasonably for a multi million dollar freighter. Subsequent improvement could probably decrease the size and cost but I doubt it would get to GPS sized dimensions - if only for the fact that the frequency requires longer antennas.

    And remember, a-Loran, b-Loran, c-Loran and e-Loran require multiple, expensive ground stations. We are all waiting to see what i-Loran will require, probably just some pixie dust and a persistent connection to i-cloud, but Apple hasn't weighed in with their plans just yet.

    --
    Faster! Faster! Faster would be better!
  10. "WWII tech" by CurryCamel · · Score: 4, Informative

    In case anyone is intersted, this slideset gives a nice overview of this "WWII tech".
    http://www.ursanav.com/sites/default/files/pdfs/news/UrsaNav%20ILA-40%20eLoran%20System%20Definition%20%26%20Signal%20Specification%20Tutorial.pdf

  11. eLoran security... by SaberCat · · Score: 1

    I just viewed a description of eLoran at: www.ursanav.com/ sites/ default/ files/ pdfs/ news/ UrsaNav%20ILA-40%20eLoran%20System%20Definition%20%26%20Signal%20Spec ification%20Tutorial.pdf and scaned for the words: security, encription, jam. Nothing. Looks like there's no provision for these...true?

    1. Re:eLoran security... by SaberCat · · Score: 1

      The eLoran system adds a data capability, so encription is an issue.

  12. Jamming by dhaen · · Score: 1

    AC is correct. Jamming GPS (or equivalent other satellite system) is trivial and has been done. It's a major system weakness.

  13. Re:Wait wait wait by mcswell · · Score: 1

    "sextant and a nice, accurate watch... it helps if you are outside and can see the horizon": In fact, the "true" horizon, which is almost never the case on land, except at the shore. (Of course, the OP is about ship navigation, so I'm being a bit pedantic.) Celestial navigation also involves several books of data, a large pad of paper, and a pencil with an eraser. Although I hear there are other ways to do the calculation now...

  14. Kinetic Kill Vehicle by haulbag · · Score: 3, Interesting

    Please understand that the technology to kill satelites has been around for a long time. Several military contractors for the US Defense Department have developed kinetic kill vehicles. They are in orbit as we speak. Their purpose is to destroy satelites by ramming into them at high velocity. They are like an anvil with a guidance system and a simple propulsion system. I know that Boeing had these back in the early 1990s. I'm sure there are hundreds or thousands of them up there by now with their targets locked in. If the US has them, you know the Russians and possibly the Chinese have them. If there is a major war between any of the major powers on Earth, the satelites will be one of the first casualties.

    Also, of course, the Chinese proved they could destroy satelites from the earth by their launch of a missile at one of their own several years ago. (Thanks for the space debris, China.)

    1. Re:Kinetic Kill Vehicle by K.+S.+Kyosuke · · Score: 1

      With the GPS sats at a distance of 20k kilometers, you'd have plenty of warning to bomb the shit out of the attacking country before the kill vehicles could even approach the satellites.

      --
      Ezekiel 23:20
    2. Re:Kinetic Kill Vehicle by lgw · · Score: 1

      There are also (far less expensive) anti-satellite missiles that a fighter can launch from high altitude to kill sats in low orbits. Geosync orbit is pretty safe, but GPS sats orbit much lower.

      --
      Socialism: a lie told by totalitarians and believed by fools.
    3. Re:Kinetic Kill Vehicle by haulbag · · Score: 3, Interesting

      With the GPS sats at a distance of 20k kilometers, you'd have plenty of warning to bomb the shit out of the attacking country before the kill vehicles could even approach the satellites.

      I never said that the first attack would be the satelites, but it very well may be. How much warning do you have when the KKV is already in orbit? All it has to do is change orbit slightly and your satelite is dead. Also, you suggest that a state would use nukes before their satelites are taken out. I don't agree. Whether you agree or not with the concept of MAD (mutually assured destruction), it is clear that the major nuclear powers do. It is quite conceivable that there could be a conventional conflict that would not escalate to a nuclear launch. In that case, taking out GPS would level the playing field for weaker nations and coalitions.

      http://en.wikipedia.org/wiki/Anti-satellite_weapon

      http://en.wikipedia.org/wiki/Militarisation_of_space

    4. Re:Kinetic Kill Vehicle by K.+S.+Kyosuke · · Score: 1

      How much warning do you have when the KKV is already in orbit? All it has to do is change orbit slightly and your satelite is dead.

      How do you "change an orbit slightly" from LEO to a GPS orbit? By using the Picard manouever?

      --
      Ezekiel 23:20
    5. Re:Kinetic Kill Vehicle by haulbag · · Score: 1

      I never said what orbit the KKVs are in or that they would need to change from LEO to MEO.

    6. Re:Kinetic Kill Vehicle by K.+S.+Kyosuke · · Score: 1

      Except that any orbit "slightly away from a GPS orbit" would be immediately suspicious. This isn't 9/11. No spacecraft gets even remotely close to those orbits without someone noticing it and remarking "that's funny".

      --
      Ezekiel 23:20
    7. Re: Kinetic Kill Vehicle by jd · · Score: 1

      A dark satellite made from an ultrablack material or using a stealthy topology simply isn't going to be seen. By anyone.

      Ion engines are slow, but they don't give off any tell-tale glare.

      The southern hemisphere has very little in the way of monitoring - a satellite traversing any great circle other than equatorial will be difficult-to-impossible to track.

      This is not a likely threat, on a scale from one to ten, the seriousness is sqrt(-1). Nonetheless, it's not zero.

      --
      It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
  15. Re:Wait wait wait by K.+S.+Kyosuke · · Score: 1

    In space terminology, it's "what a retrograde".

    --
    Ezekiel 23:20
  16. Contrast by fnj · · Score: 2

    Nice to know the grown-ups are in charge of strategic planning in the UK. Contrast the no-intellect kiddies and political scum in the USA. Congress passed an appropriation in 2008 to implement eLORAN, but some puffed-up asshat in the executive branch zeroed out the funding and nobody ever followed through.

  17. Re:Wait wait wait by K.+S.+Kyosuke · · Score: 2

    I think YOU are confused, how much energy does it take to build these satellites and put them into their orbits? THAT's what I'm talking about!

    If a long-wave LORAN transmitter with mere 1 MW of RF output power (usually, it's more) could replace a microwave sat with 25 W of output RF power, then the equivalent energy needed for running that LORAN transmitter for the projected GPS sat lifespan of 7.5 years is equivalent to burning almost 6000 tons of kerosene, without taking the electricity generation efficiency into consideration. Quite optimistically, the corrected figure would be somewhere around 12000 tons. And the 7.5 figure is for the old sats, the new ones have a projected lifespan of 15 years, so that's more like 25000 tons of kerosene. In comparison, a suitable rocket for those GPS sats could have something like 200 tons of fuel at most (it tends to be a Delta II, or an Atlas V, these days). Now what is it you were saying about "high-energy approaches"? (Also, I should imagine that those larger receivers mean more energy and materials consumed when manufacturing them.)

    --
    Ezekiel 23:20
  18. Re:LMFAO by Anrego · · Score: 1

    Shipping used to be a ridiculously dangerous thing. The navigator on a ship was probably one of the most skilled crew members, and if he fucked up, you were done.

    I honestly believe even if we did still have that skill set, if you applied old techniques to the scale of modern shipping, it would indeed be catastrophic, and not just for those at sea.

    The world now depends on international shipping. Sure, things could be re-juggled (our food didn't always spend half it's time floating across the sea from cheaper production facilities), but in the interim there would be mass problems as supply chains fell apart and things like oil, food, and materials suddenly became scarce.

    And planes would be even worse off!

  19. For civilian purposes, non-space-based is right. by Ihlosi · · Score: 1

    Positioning systems for civilian purposes shouldn't be space based due to obvious issues with satellites (expensive, hard to maintain, etc). Hopefully, at some point, we'll have positioning systems that don't require any infrastructure all. Would be nice if they could tell the position from landmarks, the sky and Earths gravity field. ;)

  20. Re:LMFAO by Anonymous Coward · · Score: 1

    Yeah, well, GPS, GLONAS and GALILEO all require multiple, expensive satellites and ground stations too. I'm pretty sure eLORAN will be an order of magnitude cheaper.

  21. Re:Existing receivers? by k6mfw · · Score: 1

    I was wondering the same. I see lots of LORAN receivers on ebay (some look ubercool industrial), low cost because nobody uses LORAN anymore. But wait, I think it is still operational on certain coastal regions, too lazy to check.

    --
    mfwright@batnet.com
  22. no common mode of failure? by fustakrakich · · Score: 1

    Um.. electricity? Without it, pray for clear skies, a sextant, and knowledge how to use it.

    --
    “He’s not deformed, he’s just drunk!”
  23. Am I the only one? by ArcadeMan · · Score: 2

    I read the title as "World War II Tech DeLorean Deployed As GPS Backup In the UK".

    Followed by "They had time travel in WW2?"

    --
    Get free satoshi (Bitcoin) and Dogecoins
  24. Re:LMFAO by hey! · · Score: 1

    Yeah, because no shipping ever occurred before LORAN or GPS. What a joke! It's not like people found their way around the globe for centuries using the sun, moon and stars.

    Sure, if a precision of 1 nautical mile (1852 meters) is good enough for you, with fixes only possible at certain times of the day. Celestial navigation is not going to keep your 200 foot beam supertanker in the middle of a 500 foot shipping channel in the middle of the day. That's like treading a needle, only you thread ways a half million tons and is traveling at 19 miles/hour.

    --
    Post may contain irony: discontinue use if experiencing mood swings, nausea or elevated blood pressure.
  25. In unrelated news... by fahrbot-bot · · Score: 1

    ... announced that they have deployed a World War II technology called Long Range Navigation system, ...

    ... millions of people around the world deploy a stone-age technology called "fire" to cook their dinners each night.

    --
    It must have been something you assimilated. . . .
  26. Re:Wait wait wait by K.+S.+Kyosuke · · Score: 1

    You still haven't built the rocket. We can make electricity by damming rivers.

    And you can use that electricity for manufacturing the rocket. So what? Everything's OK, it seems.

    Technology gets better, remember?

    So does rocket technology.

    We can make more sensitive receivers!

    But you're still stuck with large gear for longer wavelength reception if you want to make it work for maritime applications (and flying over most of the oceans). And even a lot of the Earth's land surface (Siberia, Sahara, Antarctica...) So now you have two different high-energy systems to maintain instead of one low-energy one (save for the odd launch here and there). Yummy.

    We can make solar power assisted transmitter towers! You can't make solar power assisted rocket launches.

    Actually, you can. Once you're in LEO, you can use a solar tug. That's still considerable savings over going chemically to the proper GPS orbit, if this is what you want so badly.

    The low-energy future means we'll still have electricity but not the massive infrastructure needed to concentrate that 7.5 years of LORAN into a 5 minute rocket launch.

    Why wouldn't we? And I'm not interested in that bleak low-energy future of yours. That would be the end of civilization as we know it. You can live in it yourself if you want it so badly, but don't pull me into that.

    Not to mention the fact that this humongous disparate-data-integration scheme some feeble mind here proposed might easily cost even more energy, especially to manufacture the chips capable of doing that. Keep in mind that this depends on the number of receivers. Solving the GPS algorithms is a well-defined problem, and works the same way everywhere, but integrating very diverse local data in a wide band (SDR?) would most likely require a lot more processing power - programmable processing power, because the problem is not well defined - and perhaps even quite a lot of storage (instead of solving just a few equations for the GPS solution). So now you have an SDR to receive and demodulate all those disparate sources, and a PC-scale programmable device to work out the position. There may be tens or hundreds of millions of receivers you'd have to vastly upscale in terms of programmable computational capacity (and larger batteries to power them without making people mad) just because you decided to shirk the work of two dozen spaceborne transmitters onto someone else. False economy, anyone?

    I mean, my personal energy expenditures, consciously lowered, are perhaps some of the lowest among the people of the first world, but even that's not enough to make me a total idiot when it comes to practicality of engineering solutions.

    --
    Ezekiel 23:20
  27. Good to keep that going by Animats · · Score: 1

    It's not "WW II", technology, it's late 1950s LORAN-C technology. LORAN-A was WWII. It's good to have this as a backup. Many aircraft still have LORAN-C receivers. It's good enough to find an airport.

  28. Re:Wait wait wait by K.+S.+Kyosuke · · Score: 1

    This doesn't exactly look like a low-power device, seeing as I can have a 1kw RF PA in a shoebox. Plus while some twenty-odd satellites give you global coverage, you'd need many times more LORAN stations to give you the same.

    --
    Ezekiel 23:20
  29. Re:Wait wait wait by K.+S.+Kyosuke · · Score: 1

    Yes, but historically, one of the meanings as a noun was "One who falls away or degenerates."

    --
    Ezekiel 23:20
  30. HAM is not an acronym by xenoc_1 · · Score: 3, Funny

    How come slashdotters always write it as HAM? It's ham radio, not HAM. Despite rumors, it does not stand for Highly Antique Morse.

  31. US Navy still using sextant and chronometer by perpenso · · Score: 3, Interesting

    I saw a documentary on a US Navy Aircraft Carrier, it had a relevant incident. The carrier has GPS, LORAN, inertial navigation, etc. Yet every day a sailor steps outside the bridge with a sextant and takes readings on the horizon and sun. (does another sailor do so at night with the stars?). He then goes inside and using a WW2 manufactured mechanical chronometer calculates the position of the ship. When asked why the Navy still uses such ancient mechanical technology the sailor replied that this ship is a warship and is expected to be where it needs to be regardless of whether the fancy electronics is working or not.

  32. Yeah like VHF multilateration by MichaelSmith · · Score: 1

    Its used in Australia as well, in parallel with GPS and radar. The aircraft transmits a signal, and multiple ground stations compare the arrival time.

    --
    http://michaelsmith.id.au
  33. Re:GPS can fail? by MichaelSmith · · Score: 1

    There is one switch in the US which will disable the whole system. GPS works badly for aircraft because they change altitude. Most users have a fixed altitude, so a small degradation in the system can cause large positional errors.

    --
    http://michaelsmith.id.au
  34. Re:GPS can fail? by Ungrounded+Lightning · · Score: 1

    I'm not sure how GPS can fail? There are like 26 or so satellites over the earth. I can't imagine all 26 of them going down all at once?

    For starters you need to be able to receive from at LEAST three of them simultaneously or they might as well not be up there.

    There are 26 because some will be on the wrong side of the Earth, or below the horizon, or behind a building, mountain, or thick cloud. Lose a few and you have times when you can't hear at least three that well separated from your viewpoint, so you GPS doesn't work then. Lose a lot and you can almost never hear three or more at once.

    --
    Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
  35. GLA... by antdude · · Score: 1

    I was thinking of Global Liberation Army from Command & Conquer: Generals (C&C:G). :P

    --
    Ant(Dude) @ Quality Foraged Links (AQFL.net) & The Ant Farm (antfarm.ma.cx / antfarm.home.dhs.org).
  36. The US may still get eLoran by Midnight+Thunder · · Score: 1

    If the following blog post is worth anything, then maybe the USA will still go with eLoran as a backup:

    http://www.panbo.com/archives/...

    The next question is how cheap is the most affordable eLoran receiver, and where can one be bought?

    --
    Jumpstart the tartan drive.
  37. Re: Wait wait wait by jd · · Score: 1

    The Viking version was the sunstone, which was not much bigger than an old-fashioned pocket watch.

    --
    It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
  38. re Loran by Phil+Karn · · Score: 1

    That was probably LORAN-A, with which we used to share the 160m band (1.8-2.0 MHz). LORAN-C operates (or operated) in a dedicated allocation at 100 kHz. LORAN-A was shut down quite a few decades ago.

  39. are you sure? by Phil+Karn · · Score: 3, Informative

    LORAN-C would probably be rather resistant to EMP. Like just about everything military, the transmitting equipment would be designed to be EMP-resistant, and receiving equipment on vehicles would not be particularly susceptible. It's stuff with long cables that picks up EMP. LORAN-C is certainly much more jam-resistant than GPS. The transmitter power levels are/were enormously higher, some in the megawatt range, to overcome natural background noise and antenna inefficiency. Even the large towers used are only a small fraction of a wavelength (3 km). Also, LORAN-C operates by groundwave propagation (that's why the frequency is so low) so it's not very sensitive to solar activity.

  40. good to have backups by Phil+Karn · · Score: 1

    I certainly wouldn't bet that GPS satellites couldn't be destroyed, but most anti-sat weapons demonstrated so far work only on low altitude orbits. The US systems consist essentially of lobbing a small suborbital missile up in the path of the target satellite. Destroying a GPS satellite in a 20,000 km orbit takes a much bigger launch vehicle and considerably more time, and would be much harder to conceal from US space sensors.

    Jamming and spoofing are the much bigger threats.

  41. Re:LMFAO by Phil+Karn · · Score: 1

    Because of inherent drift, inertial navigation is inherently suited only to fast vehicles that get to where they're going in just a few minutes or hours, e.g., planes and missiles. Cargo ships do not qualify. It is best combined with GPS to "flywheel" through outages (e.g., vehicles in tunnels) and so it can be automatically recalibrated whenever GPS is available.

    Besides LORAN-C, there used to be another low frequency radio navigation system even better suited for global shipping: Omega. It operated on even lower frequencies, in the 10-14 kHz (yes, kHz) range, and had worldwide reach unlike LORAN-C which was only regional. It was shut down in 1997.

  42. Its not exaxtly how it started... by Anonymous Coward · · Score: 1

    In Britain in world war 2, aircraft would fly hundreds of miles using dead reckoning (initial position, compass direction, airspeed, wind direction). If anything changed, or you had to do maneuvers to protect life and limb, you may lose track of time/distance/direction. Its bad to lose a plane because 'lost, tried flying home, crashed in ocean' or 'lost, tried flying home, had to crash behind enemy lines'. So they had two low frequency long range beacons: Cat and Mouse. Mouse was in Northern Scotland and sent a signal. A precicely timed signal (with respect to the mouse signal) would then be send from South England: "Cat" (cat chases mouse). Loran-S (nighttime use) could provide signals south of the North Coast of Scotland, east as far as Poland with an accuracy of 1/2 mile (skywave long baseline Loran). Considering they were operating at 1.95 MHz, it was 1943 and the first transistor was still 4 years away, that's not bad.

  43. I love GPS but ... by macpacheco · · Score: 2

    GPS L1C signal have 60W (a few times more on newer GPS sats) of power being irradiated by the antenna. By the same that signal travels 18000Km to the ground its down to miliwatts, in fact so weak that a one watt transmitter one Km away can still overpower the original signal. A 1 watt jammer can fit in your pocket. A 100 Watt jammer (no more than the size of a suitcase) can jam GPS for a hundred Kms easily.
    GPS works great as long as its not jammed. And the dangers are far worst when there's a signal being spoofed (artificially sending a signal that looks genuine, but has the wrong parameters, potentially leading to aircraft crashes, banking transactions recorded with the wrong timestamp, shutting down celullar towers, leading people to the wrong locationto name just one of the dozens of life threatening scenarios).
    eLoran is the only solution that can actually compliment GPS, providing it with a signal of similar accuracy to GPS L1C that can be received without line of sight to the antenna transmitting the signal 1000 Km away from the antenna.
    In my opinion destroying the Loran-C towers was the single worst decision the Obama administration made. The Loran-C signal was worthless, but the towers and adjacent building could have been shutdown and then repurposed to transmit eLoran.

  44. Is LORAN-C Truly Dead by nessman · · Score: 1

    The Seneca LORAN-C station in upstate NY between Rochester and Syracuse, while silent, didn't destroy it's tower or buildings - instead it was taken down one section at a time - and is stacked neatly in the parking lot. Wonder if it's simply been mothballed in case they need to reactivate the system?

    http://tinyurl.com/senecaloran