back to article FAA to pilots: Expect 'unreliable or unavailable' GPS signals

The US Federal Aviation Administration is warning pilots to expect “unreliable or unavailable” signals from their global positioning gear as a result unspecified tests being carried out by the Department of Defense. The Notice to Airmen, or NOTAM (PDF) said the GPS tests will be carried out beginning Thursday and are expected …


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  1. F111F

    I'll Let You Know...

    Since I live near the "o" in Georgia on that map. Interestingly, Kings Bay is the nearest point of land, were the USN has a large base...wonder what they're testing...

  2. Anon

    Manilow Magic

    Just one corner of the Bermuda triangle then?

    1. elderlybloke

      Manilow Magic

      When Aircraft fall from the sky during these tests it will be due to the aliens, force field or terrorists.

  3. rpjs


    ...Galileo doesn't look like a waste of money after all!

    1. Charles Manning


      If this is being caused by interference then most Galileo will likely have problems too since Galileo signal bands are close to GPS.

      1. Anonymous Coward
        Anonymous Coward

        ... or maybe ...

        they're testing a Galileo-disruptor? Just in case Europe ever gets it fully off the ground.

    2. Graham Dawson

      Oh, it does.

      The Chinese and the Russians already have their own GPS constellations - the russians have had theirs up for decades and the chinese are putting theirs up right now with a promise that it'll be free to use, so you're hardly limited to the US system. Why does the EU need one too? As far as I can tell it's just a big dick-waving "me too" effort, which is a label that could be applied to most of what the EU does these days. And to think we were originally promised nothing more than a free trade area...

      1. Richard Gadsden 1

        Who promised you a free trade area?

        Really? Someone promised that to you?

        I mean "ever closer union" is in the Treaty of Rome, so whoever it was was wrong.

        But "we" weren't promised "nothing more than a free trade area" but a federal state, and they can damned well get on with delivering one. Get the bloody national governments out of EU decision-making, that's what I say!

        1. Graham Dawson

          Nothing federal about the EU though

          Well, I admit I wasn't actually alive when the treaty of rome was signed so I suppose I wasn't promised anything at all. You're right that eery treaty signed since then has contained the phrase "ever closer union" but still, the talk by our pols and the media until maastricht was that the EEC was nothing more than a free trade zone and that there was nothing to worry about. The dishonesty of the promoters and founders of this union that galls me. Perhaps they were more honest about it on the continent (thought the fact that they rarely gave the people an actual choice on the matter makes me wonder) but, certainly here, we were always told that it was just a free trade area, just a convenience, just a group of pals chumming it up and that we'd never sacrifice our own national sovereignty for some "federal superstate" and that we'd always be a free and independent nation. The reality is somewhat different. Perhaps I should just accept that politicians lie, but the fact remains that they felt they had to lie in order to get us to accept membership of the EEC, and continued to lie in order to convince us to accept continuing membership of the union.

          Of course, you aren't going to get a federal union after all. The end goal of the EU's "ever closer union" is a unitary state with all power concentrated at the centre. That's about as opposite a federal arrangement as you can get. A federal arrangement would leave most legislative power in the hands of the member states, whereas the reality is that most legislative power is now in the hands of the Council and the Commission.

          1. EUbrainwashing

            The EU is a step on the road to a single worldwide governing authority

            The apparent uselessness of the UK and other EU member state's governments are (I can only assume) designed to be so corrupt and feeble that people are left feeling much as you do: wanting to get rid of them.

            This is in fact action upon a covert message, I understand, briefed to those up-and-coming future leaders, throughout society, who are groomed by the organisation 'Common Purpose' on their high-flyer training courses. They suggest to candidates that they should be deliberately building-in ineptness and failure, to their current organisations, so (as the EU progressively takes over further control) immediate, apparent and valuable improvements can be readily made.

            If one thinks this has been brought about for the good of mankind and the world, covertly by necessity so as not to frighten the stupid peasantry who, being tribal by nature, would reject the aim, you need to get with the curve. There is nothing egalitarian to be found. This is the endgame of the takeover of the world's states by the supremely rich and powerful. They care not one jot for the human heard. Indeed once we are firmly in their grip, the grip of a technological police state, the aim to to rapidly reduce the global population (and that does not just mean by means of reducing birthrates).

        2. Anonymous Coward

          re: Who promised you a free trade area?

          >But "we" weren't promised "nothing more than a free trade area" but a federal state

          Not quite how it went when we had the original referendum vote. And no, I didn't believe Edward Heath. Come back Charles de Gaulle, all is forgiven.

        3. This post has been deleted by its author

        4. peter_dtm


          ted heath promised us that we would only be joining a CUSTOMS UNION

          he lied about that - as he lied by omission about giving away the UK Fishing grounds


          the 1689 Bill of Rights (our constitution - the one the yanks based theirs on) does not allow Parliament to give away sovereignty so the whole crock of excrement is illegal to boot

      2. Mark 65 Silver badge

        @Graham Dawson

        Maybe the EU one isn't just me-too dick waving. If you don't trust the Yanks I'd hardly be putting my faith in Russia or China.

      3. Mephistro Silver badge


        It all depends on what the Yanks are testing here. My bet is that they are testing their ability to disrupt their own gps signals so enemy weapons can't use them to find their targets. The Russian and Chinese systems would be dealt with in a different manner, be it signal jamming or one of those newfangled lasers.

        It makes perfect sense. US military systems could be provided beforehand with a list of corrections to be made at any given moment, so they don't suffer any disturbance, and enemy missiles would be quite lost without gps.

        So yeah, it makes perfect sense for Europe to have an independent system. The worst that could happen is that the US asks us nicely to turn off our system for a few hours. Hopefully :)

      4. elderlybloke
        Big Brother

        Oh, it does.


        The Russian GPS system is in the process of being rehabilitated. It declined after the end of the Soviet Union. It will not be fully operational for some time.

        An unfortunate event during a launch of some satellites recently has delayed it.

        But they will get there .

        As with the Chinese and Europeans , they don't trust the Americans .

        But who does these days?

  4. Anonymous Coward

    Im lost!

    See above.

    ....I'll get my coat.

    1. Stoneshop Silver badge

      Your coat

      Do you know where it is, then?

  5. DLSmith

    Civilian signals

    If it affects the GPS equipment in aircraft, then yes, it will affect GPS receivers in phones and cars. Only military equipment uses a differnet, more accurate signal. The Air Force has the capability to turn off the GPS signals in either a selected area or the entire system if the need should arise.

    1. John Sager

      Limited effect to ground-based GPS

      The jammer or 'beam-bender' or whatever is probably located on a ship so the antenna will be limited in height, say 20m or less. The 1.6GHz GPS signal won't propagate much beyond the horizon, so the only effect to land-based GPS receivers, if any, will be in the immediate coastal areas nearby in Florida & Georgia. As the map shows, the effects to GPS in aircraft will be over a much larger area.

      1. Daniel 1

        Could be.

        However, the BBC is reporting that a Delta IV Heavy took off from Vandenberg Air Force Base, yesterday - the largest rocket ever to launch from the US Pacific coast, the "fifth flight in the vehicle's history, and the second in just two months". These are only ever used for military payloads, and this launch would fit with a polar orbital launch, according to Jon Amos.

        So the spooks are having a busy start to the year.

      2. peter_dtm


        its all done in the satellites and the decoding algorithms.

        no surface kit needed once the command signals have been sent to the constellation of satellites.

        the exact details (afaik) are of course not available - but small areas of a few 10s of square miles can be bent; through to the whole system. Not only that but it can be made to randomly ' wobble '. Basically in time of war (or leading up to war) areas can be uniquely or 'globally' affected by some very large changes in what a civilian GPS will show. Military versions can be 'told' what is happening and so correct. I had the pleasure of sailing with the 00001 serial number Magnavox Satalite Navigator for commercial marine use - back when there were only 12 satelites in the bird cage - 6 hours to get a fix from cold.....

        This is one of the reasons Shipping companies still trains people in the use of sextants

  6. Anonymous Coward

    Yes it will effect to car and smartphone GPS systems

    The GPS receiver chip is exactely the same in airplanes/cars/smartphones. In the plases there,s usually big external antenna attached innthe fuselage. In car systems there can be too, but usually less sensitive. In smartphones - well it's usually internal antenna; the least sensitive choise. In commercial avionics/naval systems the algorithms are also usually better. Thus the end result is, that the operational principle is the same, but in airplanes the system is most sensitive and in smart phones least sensitive tom pick up signal.

    Depending on the shape of beam of disortion signal (in GPS frequency) is used in these tests the non-targeted navigation systems will be affected. If the beam is highly directional (but not laser sharp), there could be minimal number of incidences to civilian navigation systems. If the beam is spherical, whole area will be blanketed with blocking signal. As civilian systems are not so well protected those will be first to black out. Nearer the signal source, higher propability to jam.

    If I should quess anything, the blocking signal is sent with targeting radar; i.e. with dish antenna, which will send quite an accurate directional signal. It's not too accurate (as laser would be) and still enough concentrated to send sufficently high energy beam at long distances. And the targetted device is a IBM type device using GPS signal for target navigation (or simulating such).

  7. Dazzz


    I bet theres a few lawsuits suddenly appear next month :-)

    1. Stoneshop Silver badge

      In which case

      they should just switch the Dislocator Beam back on on the court day. "Complainant didn't show up, case dismissed."

    2. peter_dtm


      read the Ts & Cs - use at own risk

  8. Jeremy 2


    So, might not be a good month for me to go geocaching then... Bugger.

  9. K. Adams
    Black Helicopters

    Cue Chorus of Conspiracy Theorists

    5... 4... 3... 2... 1... Go!

    1. Notas Badoff Silver badge

      When there's more than one....

      I misread your title, and now I'm wondering. What is the collective noun for a group of conspiracy theorists?

      I see suggestions for "a knoll of theorists", "a hunch of theorists"...

      How about "a whackasm of theorists"?

      (After all, it's when they get together that the screaming gets even louder and more annoying for the non-participants...)

      1. PerlyKing

        Collective nouns for conspiracy theorists

        Mental health facility? Asylum? Bedlam? Bowl of mixed nuts? This could run and run...

      2. Nick Ryan Silver badge

        Collective nouns for conspiracy theorists

        A government of conspiracy theorists? Or perhaps a parliament of them (but that's already taken by crows)

        1. Gollum_HKT


          I think it is actually a Parliament of owls, you'll find it;s a murder of crows

      3. g e


        A Redaction of Conspiracists ?

    2. HMB

      Go on! Laugh...

      Go on! Laugh... but I've already made my tin foil hat to protect myself :P

    3. Ef'd
      Big Brother

      Not a conspiracy theorist, but

      Sounds like the government is either testing GPS security or is preparing a way to defend the united states against gps-guided attacks

    4. Paul_Murphy

      A troll of conspiracy theorists?

      or is that taken by forum posters already?


    5. Wayland Sothcott 1 Bronze badge
      Black Helicopters

      It's the very definition of a conspiracy

      They are messing about with the GPS signals and have not said why.

      1. So you have several people working in secret.

      2. They are doing something that suits them but is not wanted by the rest of us.

      3. They provide a lame cover story of 'testing'.

      If this were to cause people problems would you say that it was an unfortunate consequence or the actual purpose of the operation? You are on the gullible side I am on the suspicious side. You believe in the goodness of the US military who boast about how many people they kill.

      I think it's a safe bet that these 'tests' if successful will lead to increased ability to kill people.

      1. Tom 13

        I'm not with the rest of you Sareks.

        I want them to test it, and for both purposes noted by Ef'd.

  10. Alan Firminger

    What do aircraft use gps for ?

    Navigation ! ! ! ! ! ! ! ! ! !

    Better not fly to Florida.

    1. Graham Marsden

      @Better not fly to Florida.

      I tried, but I ended up in Cuba...!!

      1. Anonymous Coward
        Anonymous Coward


        And how on earth are you accessing El Reg from Cuba?!

  11. Anonymous Coward
    Anonymous Coward

    Not a problem

    for the big, expensive boats, at least. I'd imagine not for aircraft either.

    The boats I work with (many of which are in the GoM, so in the affected area) are all DP-rated, so they've got a good number of totally independent positioning systems. Acoustics (LBL/USBL/etc), tautwire, inertial, and the good old fashioned compass.

    Planes can always home in on radio nav beacons, and get pretty accurate position updates from ATC so they'll not have too much trouble either.

    The REAL victims here will be the ill-prepared/useless civillians whose Sat Navs no longer work. There will be people sat crying at the side of the road, mark my words!

    1. Anonymous Coward


      "The REAL victims here will be the ill-prepared/useless civillians whose Sat Navs no longer work. There will be people sat crying at the side of the road, mark my words!"

      They manage to drive into rivers with GPS, I'm sure they'll manage without. Although this time they won't have an excuse.

      1. Mike Richards Silver badge

        Can't wait for the headlines

        Bearing in mind both disruptions are in areas famed for their wackos we should expect some hilarious news stories.

    2. Anonymous Coward
      Anonymous Coward


      Paramedics. The police and fire department will also have a few problems having to use maps, but those two or three minutes diffrence GPS makes over a map makes all the diffrence if someone has a heart attack.

  12. Anonymous Coward
    Anonymous Coward

    not just the handsets - networks too

    Most of the 3G mobile networks use GPS to derive timing (CDMA/EVDO networks, not so sure about GSM and its variants), so messing up GPS availability could affect the network side as well. The short outage time reduces the overall effects of the jamming, as it is standard to include timebases/oscillators to carry the site through any fades etc.

    This would also apply to any network time reference clocks that are fed by GPS. Likely any timebase currently in operation will fall back to its internal oscillator to carry it through; what will probably happen is that any attempt to bring up a reference clock based on GPS during the outage will fail as it won't be able to find/lock a signal to seed its internal reference clock.

    This capability has always been understood to exist in the GPS system, but to my knowledge not exercised. As such this might be an interesting test of the system to see what falls apart! At a minimum it would be funny to watch the tom-tom-tards attempting to function.

    1. Pav Lucistnik


      GPS timing in CDMA/EVDO system is used to synchronize pilot signals so only activity related to detecting neighbouring cells will be affected. Typically this means possibility of dropped calls on handoffs. But I believe 45 minutes is not enough to produce significant drift.

      GSM is unaffected, UMTS/3G is unaffected. Not sure about LTE.

    2. peter_dtm

      frequently exercised

      try before the assorted gulf wars and in Bosnia - anywhere the US military (or some very very favored allies) are in any form of war preparedness - even for training. It just doesn't happen very often in the continental USA. It used to be less noticed - though Notice to Mariners have carried these warnings since the 80's (obviously not for Bosnia). Mil Spec versions get automatic corrections

  13. Swiss Anton

    Differential GPS blocker?

    The big FAIL with GPS is differential GPS - even when the civil system is broadcasting a degraded signal, differential GPS allows the bad guys correct the positional error, and so be as accurate as the "secure" military grade signal. Maybe the US Gov has found a way to defeat differential GPS, and is now testing it.


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