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Doubts About Future GPS Reliability

Posted by Zonk on from the ground-control-to-major-tom dept.

loped_index writes "IT Week reports that the U.S. GPS system is in a delicate state, and that full coverage could be lost if older satellites fail faster than the current rate. From the article: 'The system relies on a network of satellites, which cannot be repaired once launched and have a limited lifespan. Sixteen of the present 28 satellites were built to last seven and a half years, but are now between eight and 14 years old. Twenty-four satellites are required for full coverage.'"

19 of 213 comments (clear)

  1. EU's Galileo by innerewut · · Score: 1, Insightful

    So maybe the US will stop its attemps to prevent the European Galileo...

    1. Re:EU's Galileo by Anonymous Coward · · Score: 1, Insightful

      Several US firms - and the US governement are active in the development of Galileo as even the most basic search will turn up.

      Yes, and those same searches will reveal the reason that the US government is active - because they want the ability to unilaterally disable it if they so choose.

    2. Re:EU's Galileo by Anonymous Coward · · Score: 5, Insightful

      Let me get this straight. You nearly praise the European nations and call the US incompetent, despite the EU-related solution is over 4 years off, not to mention have questionable delivery systems themselves.

      You take the word of a UK individual who, like folks anywhere in the world, gives talks to promote their opinion that are largely unsubstantiated unless they are privy to manufacturing data and known defects which allow him to, within reason, truly call into question satellite failure en masse. I doubt a UK RAF person will know the intimate details of the satellites. What we do know is their failure rate to date.

      It's not like nothing is being done with this problem and the problem is not unknown or being ignored; the US has known about this for some time now. Our delivery systems have had problems and huge delays (space shuttle, rockets blowing up), yet we still have been managing to replace the birds that do croak. And are replacing them next with longer lasting birds.

      You overlook the fact that many satellite systems are overbuilt and typically do last well beyond their expected lifetimes. Not all do, but a good number have (classic would be the Voyager; one still is running rather well). Until these systems start dropping rapidly faster than we can replace them, I don't see the issue. 4 of them could croak now, and you'd still get accurate info. If a 5th dies, we have one waiting to be launched already and would likely ramp up replacement schedules. If a 6th dies before all that, it depends on WHICH it dies and WHERE you are to determine if it may affect you directly.

      You trust this same Old World Europe at the expense of the US, yet look at the recent examples of them deliberately trying and "warning" regarding the domain system (which is something that could have occurred at any time prior anyways).

      You use this as an opportunity attack ad hominum US diplomacy, when that has little to do with satellite failure and more to do with their tactics of trying to get their own system (Galileo) up.

      I'm not a bible thumper. And yet even I know the problems with the proverb you quote and at the very least, it points to lack of real world experience on your part. Anytime I've spoken softly, the other person being receptive listened, but they weren't, I've watched people get pushed around and one person punched. Anytime I've yelled at someone, they overwhelmingly back down or at the very least snap from the focus, if temporarily, from the object of their violence. I just choose to yell when the situation merits it and that's not often, only when I've or another has been physically threatened and do so then to try to avoid or head off fights.

      You attack the right, making no distinction between it and the religious right, just to be critical of the US, meanwhile the EU (multiple nations too) kisses the ass of some of the most suppressive fascist and religious states in the world. Freakin hypocrite. Anytime the Old World gets involved in diplomacy, nothing of substance positive comes about to improve the world order. It's not like the EU is doing this out of the goodness of their hearts either; they want the markets, a price cut, the membership, the money just as well if not more so than the US counterparts.

      There will always be those who read a story about "US companies do [questionable or suspected evil activity]" and say, damn, it's all the US's fault, never asking or researching the EU or any other nation's track record on that same matter. But if the EU ballerinas in and bends over before doing a twirl and says "all will be okay, we're here", you're more inclined to take their word for it.

      You want to doubt and disagree with the US government? Good. I'm with you. But don't think that because you do and can that the US government is worse than some other half-baked government out there; that's a totally different set of standards and questions which you certainly have not addressed yourself.

    3. Re:EU's Galileo by theLOUDroom · · Score: 4, Insightful

      Thus, being able to "just keep up" with the current failure rate will not be sufficient to prevent the system from collapsing.

      But the implication that we're only able to just keep up is false.

      We're only launching that number of satellites per year because that's how many we need to provide adequate redundancy, not because it's the best we can do. We could send up more, but it would be a waste of money.

      What several posts fail to understand (e.g., grand parent or a few posts in parallel threads) is that the failure rate of a system is not constant over time

      I understand this concept, but what you're failing to properly acknowedge is that:
      A) The system is redundant
      B) The failure rate to needs to increase by orders of magnitude in order to outpace our ability to replace satellites.
      I highly doubt that the stastical data supports such claims.


      Go ahead fit the standard function to the availible data form the GPS satellites the have already failed. I bet it's going to agree with the course of action the the US is taking. Why? Because they can do the same math you can. As a matter of fact, I be they have even better data they don't publish.

      I am not trying to enter into the politcal side of this discussion, and I agree that the author of the article may have is own motives, but this is simply not relevant to the logic of his argumentation.

      There are gaping holes in his logic. Is it more likely that he's:
      A) incompetent
      or
      B) pushing an adgenda?

      --
      Life is too short to proofread.
  2. Yada yada by Red+Flayer · · Score: 5, Insightful

    Is it just me, or does everyone else also realize we're still capable of launching new satellites into orbit?

    Is there a concern about current GPS-enabled devices reading signals from new satellites?

    I'd be shocked if there is not money available in the Pentagon Budget, or elswhere, for replacement of needed satellites. Then again, cutting funding of absolutely necessary programs is a great way to dodge real budget cuts... since there will need to be a "special appropriation" to cover the shortfall.

    --
    "Trolls they were, but filled with the evil will of their master: a fell race..." -- J.R.R. Tolkien on Olog-hai
    1. Re:Yada yada by Rakishi · · Score: 4, Insightful

      Yeah, why replace them when they're still working fine. That would be a waste of money, extra sats which age and provide little benefit. I mean, unless 5 fail in the time it takes to get a new one up there is no problem. Given that only 2 fail per year I don't see that happening anytime soon.

      I mean, come on look at this idiotic statement:
      'Bonnor said launches of new satellites are "only just keeping up" with current losses of around two satellites per year.'

      What they hell is the US supposed to do, send up more satellites than they lose and waste money keeping up sats when only 24 are needed (+ a few redundant ones)?

  3. Re:Something doesn't make sense here. by $RANDOMLUSER · · Score: 2, Insightful

    Um, they're in orbit?

    --
    No folly is more costly than the folly of intolerant idealism. - Winston Churchill
  4. Re:Well... by merreborn · · Score: 5, Insightful

    we're close to the point where we don't need satellites

    That idea falls apart when you're in, say, the alps. Or the sahara. Or most of the planet.

  5. No news here by adsl · · Score: 5, Insightful

    If you put up satellites at a quicker rate then you have too much redunancy in the skies and too much junk in space. It's all a balance, as it should be. Another timely "This is why Europe should run everything" spin story. Be good if Europe invented something really new and useful, for American's to play with (for free)....

  6. Why this scare tactic? by rolfwind · · Score: 2, Insightful

    The US government/military has a humongous interest in keeping the system up - why be scared about it? It will keep plodding along.

    Or am I missing something here?

  7. Ahh, yeah.... by killtherat · · Score: 5, Insightful

    Given the military's dependence on GPS, do you think they would allow one second of interuption? And they use it on almost every corner of the globe. They would notice holes in service much sooner then you ever would.
    Call this article what it is, FUD to prop up EU's Galileo.

  8. They're up longer BECAUSE they didn't fail by MDMurphy · · Score: 5, Insightful

    It's not that the satellites were just left up there longer because they couldn't be replaced, it's because they've lasted longer than they were intended to. Kind of a "if it's not broke, don't fix it" philosophy.

    With redundant satellites and constant monitoring from the ground, it's possible to let one go until it fails, mark it as "bad" and replace it a little later.

    The article is wrong about 24 satellites being required for full coverage. A full set is 21 with 3 as spares.

    The article also implies that the satellites are failing at greater than planned rate, when the opposite is true.

    It's probably just a coincidence that the guy quoted in the article, Norman Bonnor, is a backer of the European counterpart to GPS: Galileo. It's not like he'd have an interest in bashing the GPS system to help further justify Galileo's funding?

  9. Re:Well... by Anonymous Coward · · Score: 1, Insightful

    Not to mention that non-government controlled devices could intentionally misrepresent their location.

  10. Re:hmmm... by LnxAddct · · Score: 2, Insightful

    The article is pretty much an advertisement for the European Galileo system.
    Regards,
    Steve

  11. Re:I don't care who does what with who by Poltras · · Score: 2, Insightful

    "Only wimps use tape backup: real men just upload their important stuff on ftp, and let the rest of the world mirror it." [Linus B. Torvalds]

    --
    Of Code And Men
  12. Such BS by chadseld · · Score: 3, Insightful

    There is nothing to worry about, this article is inflammatory. Do you have any idea how many weapon systems rely GPS? I work in the defense industry, GPS is everywhere. When the current satellites start falling down, we will send up more. In fact, those plans to 'weaponize' space are mostly a reaction to the realization of how important the GPS system is. It is a single point of failure and must be protected. Do you really think the armed forces are going to let the system fail due to neglect?

  13. Re:Well... by Asetilean · · Score: 2, Insightful

    And, last time I checked, it was looking kinda difficult to build stationary cell towers on the ocean, nevermind a pesky lack of demand...

    Plus, air traffic is now highly dependant on GPS and most cell antennas aren't aimed up at the sky.

    So, for imprecise civilian needs (tell me how to go from here to there), a cell tower based nav system might be fine. But GPS is capable of providing a whole lot more than that.

  14. Absolutely by Sycraft-fu · · Score: 4, Insightful

    People seem to forget that GPS is a military system, developed for military purposes. They opened it up for civilian use and that's wonderful, it's been a massive boon, but it was developed for the US Military alone. It is also the prime location system for just about all military units, from individual soliders up to large ships these days. While I'm sure the military COULD function without it, it would seriously screw things up.

    It's a strategic asset, and they aren't going to let it fail. If it was all private run, ok maybe then there'd be a worry that someone would decide to cut costs on it and let it slide, but it's the military's toy and there's no way in hell they are letting it fail.

    All the military implications aside, US commercial intrests rely very heavily on GPS these days and letting it fail would also not be in the economic intrest of the US government.

  15. Lot of old stuff you've listed there by Anonymous Coward · · Score: 1, Insightful

    The newest one you've listed is 65 years old. Most of it is starting to push into hundreds of years old, if not older. Got anything new?