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 …


This topic is closed for new posts.
  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 Silver badge

      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 Silver badge

          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

        @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


        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

      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

      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

      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
      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. Anonymous Coward
        Anonymous Coward

        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.

    1. Trygve Henriksen

      There's probably a solution already...

      A differential GPS guidance system requires a continually-broadcasting transmitter on a fixed location.

      What are the odds that a missile can home in on something like that?

      1. Swiss Anton

        Can't always kill DGPS with missiles.

        Sorry, I should have said, designing in the ability to degrade the civil GPS was a big FAIL. There are many way to implement a DPGS system without having to use fixed locations and/or continuous broadcasts - and these alternatives would not be vulnerable to a missile attack. The only way to defeat DPGS is to switch off the civil GPS signal. So, back to the original El Reg article - why on earth would anyone now want to even temporarily switch the civil GPS back into its degraded mode.

    2. Ru

      dGPS is no substitute for military precision GPS

      To use dGPS properly, you need a fixed base station at an accurately known position, and you need a radio link between the base station and the mobile unit so the encrypted, high precision differential can be calculated and a more accurate position reported to the mobile unit. There are almost certainly some major restrictions on the distance between the two stations, and differences in altitude, and speed of the mobile unit, etc etc.

      Fixed stationary unit? Sounds like a precision guided munitions victim. Mobile unit with chatty radio transmitter? Sound like something that will be easy to spot and/or jam.

      Bottom line? dGPS is great for civil engineers doing surveying. Its pretty ropey to plan a military operation around.

  14. Anonymous Coward
    Anonymous Coward

    read John Sager comment above

    most likely this is just a test of gps jamming, or overcoming such jamming (and possibly both).

  15. Anonymous Coward
    Big Brother

    It's an echo from '43

    Believe what you will, I've *seen* 'The Philadelphia Experiment', we all *know* what they're really up to...

  16. Anonymous Coward

    Pilots to FAA:

    "how will we tell?"

    1. Paul Smith

      AC @23:46 - How will we tell?

      Aircraft have multiple navigation systems including GPS, INS and VOR/DME and each system is constantly being compared to the others to spot exactly these sort of mistakes. It is why so few pilots end up driving into rivers etc.

    2. Anonymous Coward

      Come now,

      you know the US military established that policy decades ago: Don't ask. Don't Tell!

  17. Randomyachtie

    My tupence worth

    To clarify a few for the comment above:

    - Whilst the chart shows the origin of the test out at sea, it is most likely that any jamming system would be airborne flying above the ships, therefore drastically increasing its effective range both to airborne and ground receivers.

    - Differential GPS can only correct relatively small timing (clock sync) errors and atmospheric / ionospheric errors of the satellite signals by comparing the computed position to the actual known ground position. This will completely fail if there are no satellite signals to compare ie signal jamming, or if they are testing a new system which is able to induce variable unknown latencies and errors into the satellite signal.

    Interestingly Cellphones and Assisted GPS receivers (AGPS) may well fair much better than DGPS and aircraft systems as they can fall back on cell tower triangulation which whilst much less accurate, is an independent system and so depending upon the durations of the disruptions and the algorithms involved in the specific receivers they may be able to maintain a rough track plot.

    Of course all commercial aircraft also carry Radio Direction systems which are used for navigation so a bit of GPS disruption shouldn't affect your transatlantic flight to America.

    1. Phil 54

      I would imagine

      that the US military has taken into account "...that any jamming system would be airborne flying above the ships, therefore drastically increasing its effective range both to airborne and ground receivers." when giving the range. After all, they designed the GPS system and the (presumed) jamming technique.

    2. Anonymous John

      Re My tupence worth

      Let's hope the plane with the jammer isn't navigating with GPS.

  18. Martin Gregorie

    And California

    There's similar test based at Porterville, CA that takes place during the same dates:

  19. Cunningly Linguistic

    A title from afar

    Is ET scheduled for a diplomatic visit?

  20. Jeremy 2

    Didn't seem to affect reception...

    I left the GPS out in the back garden near Atlanta from an hour or two before the test supposedly started until just now, 30 minutes or so before the scheduled end. The tracklog never wandered more than little bit from it's actual location (within 10m ish throughout, and 43m off for a split second) which is perfectly normal.

    I'm sure they were just covering their arses issuing the notice - just in case something unexpected and they got fingered for it. If they were going to do something that they knew would _actually_ hit GPS accuracy to any significant degree, there would have been a bit more warning, I suspect, given the potential safety implications of loss of civilian GPS these days (the emergency services use it for starters).

  21. JaitcH

    If there are any accidents or odd disappearing acts ...

    they can always blame it on the Bermuda Triangle phenomenon. (See: < >) Users should also read he terms and conditions of their GPS devices - most have clauses disavowing responsibility for everything.

    This makes 'nature' responsible and you can't sue 'nature' even in the U.S.A.!

    This service interruption is another reason for having a Euro system.

  22. bitmap animal

    Also (car) alarms

    There are / where some car alarms that were based on the car moving when not authorised and I think this may also be use to allow certain systems to only work at their defined ‘home’. If this affected those there would be an awful lot of alarms and failed systems for people to contend with!

    This probably won’t affect land based as per the earlier comments so shouldn’t be a problem in these particular tests but is another eye opener into the impact of civilian GPS failing.

    1. Dave Rickmers

      Remember when all the garage door openers in Vegas failed?

      At least this time we got a vague (CYA) advance notice...

  23. John Smith 19 Gold badge

    A few GPS notes

    GPS has been due for upgrade for some time using IIRC new coding methods and frequencies. The ultimate live test of this is to broadcast them and see what happens. I think the plan was to retain the current ones (at least the civilian) and replace/upgrade the military channel.

    The original purpose of the civilian channel was to tell military receivers what time of the week it was to start searching for a code lock. Switching off the civilian channel would in principle prevent a military grade receiver locking on to the signal. It also provides a way for military receivers to cancel out the random ionospheric delays which are a major element of improving the accuracy of timing in military receivers. I'm not sure if that just requires the reception of 2 signals sent from the same satellite at different frequencies or it would need the civilian channel to continue sending its time code.

    The spread spectrum civilian code is 1024 bits long sent at a bit rate of 1.024 Mbs encoding a data channel of 50bps. This means the code repeats about a thousand times a sec. The military code is around 2^43 bits long and repeats on a weekly basis.

    In principle a military receiver already locked on should stay on lock.

    This would be a pretty big issue if you're on an aircraft using a cat3b certified blind landing system which often use GPS and the WAIS corrections to meet the performance targets.

    Mines the one with series of articles on software decoding of GPS with a Transputer in the pocket.

  24. mhenriday
    Big Brother

    Yet another demonstration

    of why Europe and ESA were wise to go for Galileo, i e, a satnav system not under the control of the US military. Posted a comment to this effect on another thread dealing with Galileo a few days ago, but as I made the mistake of also responding to a posting which contained a not entirely favourable reference to a certain Reg contributor, my comment, along with that of two others, was removed by the censors who maintain discipline on the Reg fora. Hope they will find the present posting so innocuous that it is allowed to pass !...


    1. Sarah Bee (Written by Reg staff)

      Re: Yet another demonstration

      Sure. I'll reject your comments randomly in future though, just to keep your paranoia topped up.


      The Reg Censors

      1. mhenriday

        Just as long as you keep it random,

        Sarah - shall we say one of ten ?...

        My best to Mr O !...


    2. peter_dtm


      Galileo will have exactly the same type of ability; only under Brussels control; some how I trust the Yanks; Ruskis and Chinese more than Brussels

  25. JMB

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

    Don't the aviation authorities always advise pilots not to rely completely on GPS?

    Similar tests happen off the British coast a few times a year, nothing unusual about it.


    1. Templar

      Don't the aviation authorities.

      They do, but its nice to know that its on the fritz otherwise you'll be concerned about it not working or giving a totally incorrect reading.

      VOR and NDB are the radio nav aid's one uses.

  26. Will 19

    Haven't we been here before?

    It happened in Cornwall a few years back:

    There were lots of complaints that it was tourist season and everyone would get lost. The event passed pretty much unnoticed.

  27. Anonymous Coward
    Black Helicopters

    It would appear...

    ...that none of you have realised just how simple it is to disrupt radio signals.

    It's simplicity itself.

    1. Broadcast a much stronger than the original signal you intend to block or disrupt.

    2. Modulate it with white noise.

    Result? A totally useless frequency.

    The trick (and not a very clever trick at that) is to enable this to be performed on a series of frequencies, or even a wide segment of the RF spectrum.

    I'm willing to bet that this is what all the tests are aimed at confirming. It's relatively simple tech, but due to the bandwidth and power output required, not that easy to accomplish.

    Anonymous, 'cause I don't want the lads in black knocking at my door!

  28. EmperorFromage

    Jamming could reach even further

    Select region: Gulf-Caribbean

    Strong tropospheric ducting is forecast, meaning the jamming signal could be ducted and picket up hundreds and even thousand miles away. I bet they didn't think of this...

  29. asiaseen

    The navigator's motto is

    Man is not lost, merely uncertain of his position.

    Commercial aircraft shouldn't have too much of a problem. They have inertial systems as the primary navigation mode. If you have ever looked at the terminal wall at an aircraft stand, it has the exact geographic coordinates painted on it for setting up the IN before flight. GPS is used to keep it up-to-date. It's the private aircraft that will be most affected because they don't have IN (or don't know how to use it).

    1. peter_dtm


      the radio/electronics officer/engineer/tech's is

      I know exactly where I am - it's the world that seems to be lost

  30. Wayland Sothcott 1

    Special Relativity

    The GPS system has to be corrected for Special Relativity caused by speed and gravity otherwise it would be miles out. Maybe they are switching on some sort of time warp machine in the Bermuda Triangle. The effects of this might be undetectable to the public except in time sensitive systems such as GPS.

  31. Nameless Faceless Computer User

    Non issue

    Commercial pilots do not use GPS for navigation. They use a series of land-based beacons such as VOR's. Some private pilots flying light aircraft may use GPS since it's easier, but only during VFR (Visual Flight Rules). On this occasion, private pilots will simply switch over to the older system.

    1. Paul Smith

      Re: Nameless Faceless@12:08 - Non Issue

      "Commercial pilots do not use GPS for navigation." - Fail.

      Commercial pilots use GPS, INS, VOR/DME and the have been known to look at compasses, maps, and even out the window. Have you heard of RNAV, or GNSS approaches? These rely strongly or exclusivly on GPS. The 45meter deviation reported by one poster earlier is enough to completly miss a runway. That might proove to be an issue, don't you think?

      VFR stands for Visual Flight Rules - that means lots of looking out the window. GPS is handy because it can tell you where to look and what you can expect to see, but under VFR, it is no different from having a map. Quite a clever map, admitedly. I think what you meant, and completly failed, to say, was that private pilots flying light aircraft under IFR (Instrument Flight Rules) rely heavily on GPS navigation, but do not have the luxury that commercial pilots have of knowing how accurate their navigation data currently is. For them, 45meters out is not a huge issue, but suddenly fluctuating data can serious upset an autopilot.

  32. Anonymous Coward
    Thumb Up

    Proof that the EU does need Galileo

    As it would be for safety critical applications like aircraft navigation, this alone justifies the investment in Galileo.

  33. Malcolm Melville

    Boscombe Down

    In the UK there are often NOTAMs around Boscombe Down where similar tests take place regularly.

  34. XMAN

    Safe to assume

    I think it would be safe to assume that they're testing hardware to block GPS signals of in-air devices. E.g those pesky gps guided missiles.

  35. Annihilator

    Will not affect land-lubbers

    If you read the full briefing, the further out from the point of origin, the higher the problems occur at. It's effectively a hollow inverted cone of interference. At the widest point, the interference is at 40,000ft (FL400). Think about it - if it were affecting at ground and sea-level, they would have issued a similar notice to the affected shipping lanes in the area.

    What will be interesting is to see what's stationed at 304906N/0802811W, the source of the experiment I assume.

    1. Richard Mason

      California is a cone as well

      The notice for the test in California also details an inverted cone as well ranging from 185NM radius at 4000ft to 345NM radius at 40000ft. The centre for the California test appears to be the side of a mountain in the middle of nowhere.

      1. PT

        Mountain in the middle of nowhere?

        I can believe that. I was out in the mountains west of Death Valley last year and my GPS started telling me I was off the coast of Bermuda, 200 feet below sea level. It didn't tell me the truth again until I could put a mountain between it and China Lake (Naval Air Weapons Station).

  36. Bernard M. Orwell
    Black Helicopters


    Anyone who believes there is no such thing as conspiracy in this world is terribly naive.

    Anyone who denouces conspiracists as 'nuts' is simply buying into the sanitised government/media version of the world. To them I say enjoy your lives but remember not to watch any history documentaries.

    Especially on something called Watergate, for example.

  37. Anonymous Coward
    Anonymous Coward

    No problems detected

    Here in SC, no problems to report, at least from one person.

  38. Anonymous Coward

    Isn't this a plotline from Tomorrow Never Dies?

    I do hope this doesn't start a war caused by Elliot Carver and his pesky meddling with the GPS signals over the South China Sea....

  39. Mike Banahan

    Anybody got a sextant?

    And (for ships at least) an accurate watch, a sextant and knowledge of how to use it will get your position to within about a mile. Unless it's cloudy, oops.

    I doubt if any aircraft still carry them or have anyone who knows how to use them.

    Ebay usually carries a few - I've tried a plastic Ebbco for £20 which isn't much less accurate than a Freiberger I picked up for about £350. The latter is a fabulous piece of optics and engineering but overkill for a casual sailor.

  40. s. pam Silver badge

    Clearly the Reg Ain't Read Wired recently?

    The clues are here guys looks pretty clear with the footprint of those systems if you look on Jane's Aviation or Aviation Leak and Wrecknology websites what could be going on....hmmmmmmm

  41. Alan Esworthy

    I know

    I've got inside information and so I'll tell you exactly what's going on. The US govt is...hold on, there's loud banging at the door. Be right back.......[NO SIGNAL]

  42. Anonymous Coward

    Erm...seems pretty simple enough (conspiracy alert)

    1. GPS - no longer globally used as 'hostile' nations and some allies go it alone with equivalent systems.

    2. While GPS is predominantly in public use, its main use at some more detailed levels was and always has been miltary.

    3. It stands to reason, those allies and hostile states have military uses too.

    4. Therefore ensure you can disrupt their systems if they were used against you.

    5. Part of that suggests that a hostile nations fall-back is they would use your own system against you.

    6. Therefore, without disrupting a potential opponents system (an act of war) you must do it to your own.

    In both disruption scenarios, if you can take over the signal and make it seem to the guidance systems in inbound missile that they are on the wrong side of the globe, you might have a great defence shield.

    Strange that the coverage for this test is similar to where many birds fell out of the sky.... keep your eyes peeled if you live in this region. Other reasons for birds falling is likley XBR defence systems when they track in a reduced arc sweep that zaps a flock many times in quick succession. Remember, birds use geomagnetic navigation too. Although disruption to this would suggest some usable output products from the HAARP project.

  43. Tempest

    Won't affect Garmin users as it will ...

    simply feel like an ordinary occurrence when using Garmin maps.

    Who knows, this induced aberration might even correct the errors and make even Garmin more accurate.

  44. phil8192

    Forget GPS

    In paper maps and magnetic compasses we trust, along with an accurate crystal clock or wristwatch.

This topic is closed for new posts.