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US Coast Guard Intends To Kill LORAN-C

Posted by kdawson on from the we-will-always-have-signals-from-the-sky dept.

adaviel writes "LORAN (Long Range Aids to Navigation) is an electronic navigation system using low-frequency radio, used by many boaters (including me) before GPS. It has an approximately 200m accuracy and is a functional replacement in case GPS fails or the US implements selective availability in time of war. The US Coast Guard, part of the Department of Homeland Security, intends to turn it off starting February 8." This is in spite of $160M spent on modernizing LORAN stations over the past 10 years.

12 of 316 comments (clear)

  1. hmm by nomadic · · Score: 5, Insightful

    It has an approximately 200m accuracy

    Wow, I didn't know it was that inaccurate.

    and is a functional replacement in case GPS fails or the US implements selective availability in time of war.

    If the US implements selective availability of GPS, they can certainly also just turn off Loran-C.

    1. Re:hmm by mschuyler · · Score: 5, Interesting

      Actually, yes. When I was commercial fishing on a troller in Alaska we used Loran grid coordinates, spoken in Danish, to tell our brothers where the fish were. No one else could understand us. If we said "Over and out" the conversation was finished, but if we said "I'm off," that meant to change frequencies, tell how many King's you'd caught, and give the coordinates. Without the Loran our sneaky ways will have to be changed.

      --
      How about a moderation of -1 pedantic.
    2. Re:hmm by afidel · · Score: 5, Informative

      GLONASS has 16 operational satellites currently with 2 new birds coming online and one in the process of being decommissioned, they need 24 for full coverage. There are (expensive) commercial units with support for both GPS and GLONASS primarily targeted at surveyors because having the additional signals available makes very accurate (sub-meter) locks significantly faster. There are also commercial providers of GLONASS only units (Septentrio, Topcon, JAVAD, Magellan Navigation, Novatel, Leica Geosystems and Trimble Inc according to wikipedia) if you wanted them. The only reason the constellation will be back to full coverage is that the Indians pitched in a bunch of money to fly a bunch of the new birds. As of 2007 it has been official that the signals can be used for free by consumers in any country free of charge (not that they could stop you before since most devices don't need the L1 key to get accurate positioning, it just speeds things up).

      --
      There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
    3. Re:hmm by plover · · Score: 5, Informative

      Are you always this paranoid about the U.S. government? Seriously, the Russians have had their version of GNSS flying for 35 years, and you can buy a completely non-American GLONASS receiver that will give you the same data as an American (made in China, of course) GPS receiver. We know full well that we don't have a monopoly on global navigation.

      They are shutting LORAN-C off because it's expensive to maintain a separate system, especially one that is not nearly as accurate as GPS, and is at risk of terrestrial attack (a determined terrorist group could easily destroy a critical LORAN-C tower, but the same group does not have physical access to the GPS satellites.) In addition, its consumers are not widespread, and are already using GPS for their primary navigation systems.

      You should think before you make up bogus conspiracy theories. They make you look kind of crazy.

      --
      John
  2. Costs and benefits by MaXintosh · · Score: 5, Insightful

    This is in spite of $160M spent on modernizing LORAN stations over the past 10 years.

    There's this thing called the Concorde Fallacy that is relevant here. It doesn't matter how much money you spent, all that should matter is anticipated future costs and benefits. And I think for a 200m redundant navigation system, future costs >> benefits.

  3. Comment removed by account_deleted · · Score: 5, Interesting

    Comment removed based on user account deletion

  4. One down, many more to go. by viking80 · · Score: 5, Informative

    There is absolutely no use for Loran C. You currently have the following systems in place backing each other up. Many cheaper and better. In fact, many of these most likely will vanish soon.
    1. GPS, LAAS, WAAS, DGPS
    2. Galileo, EGNOS,
    (as well as GLONASS and Baidu)
    3. Inertial
    4. Visual navigation (computer with terrain sensors, including sonar and radar)
    5. Also VOR, DME, ADF, NDB, ILS, TLS, MLS, Marker beacon
    with the final fallback
    6. Old fashion navigation with compass, light houses, sextant, chronometer etc.

    --
    don't cut it off www.mgmbill.org
  5. Re:Accuracy by ivan_w · · Score: 5, Interesting

    SA made GPS accurate to 10m.. With the "SA" feature disabled, you're down to 2m... And with Satelite enhancements, it's more like 20cm !

    But that's irrelevant.. Because SA was intended to disable any enemy force from using GPS for accurate positioning - until they realized D-GPS (Differential GPS) made the whole point moot (you take a reference point - you send the signal to the receiver - And therefore - the receiver can deduce the SA introduced clock error - because now you have a ref point .. And believe it or not - it is a United Stated Uniform service - the US Coast Gard - that came up with it to overcome the artificially introduced uncertainty).

    However, the military still keep exclusive use of the 1Mhz band (with the 10Mhz being public) - for the only purpose of being able to make real time measurements on tropospheric distortions - so - what happens - is that the military can make 1m accurate reading WITHOUT sat aids.

  6. Complimentary Systems by Anonymous Coward · · Score: 5, Funny

    What a complimentary system sounds like: "My, what a nice position. That lat/long looks so good on you."

    Of course, such a system would only be useful as a complement.

  7. Re:The name Bowditch comes to mind by dziban303 · · Score: 5, Funny

    Who would operate a 600ft ship in coastal waters ?

    Sailors, I guess.

  8. Re:LISTEN, TERRORIST-COMMIE LOVERS !! by MrNaz · · Score: 5, Funny

    As trollish as your post is, I would wager that it is more than a little likely that LORAN is being turned off precisely because it is a beacon based system that selective availability cannot be implemented over. There is no way that LORAN could be used to provide positioning data to select parties.

    Personally, I don't think this is a safe thing to do. Maritime equipment is notorious for being long lived. I would highly doubt that there are no boats that are still dependent on legacy systems. Well, I guess this is one way to ensure that they upgrade.

    Feb 8:
    First Officer: Captain! We've lost navigational systems!
    Captain: Damn! That can mean only one thing. Arm photon torpedoes!
    First Officer: Err.... we're a 32 year old fishing trawler and we don't have any...
    Captain: Quiet! There's no time! Transfer engineering to the bridge and make sure we've got warp if we need it.

    --
    I hate printers.
  9. Re:How about by the_other_chewey · · Score: 5, Informative

    [...]Find a port when you're somewhere random in an ocean?

    LORAN is pretty much useless for this. What almost everyone here seems to be missing is:

    LORAN coverage is very limited.

    There's e.g. none at all on the southern hemisphere, and in the northern it isn't much more than
    a coastal navigation help either.

    Have a look at the map.

    LORAN is in no way a useful backup for GPS except in a very small part of the oceans.