When I was younger, I was a sort of  low-calorie version of a survivalist. Vaguely worried that Janet Reno, the Red Army, or possibly even aliens  might be coming, I bought a large gun safe and proceeded to fill it with a rather thrilling assortment of firepower. I raised my bed up on blocks  and stacked cans of survivalist chow underneath. I studied  and practiced wilderness survival techniques.  It was a harmless activity really, and not entirely unreasonable given the lurking San Andreas fault which to this day stands poised to wipe out Northern CA.  When the  Big One came, I rationalized, I would protect my  cans of Dinty Moore till they pried them from my cold dead hands.

That phase of my life concluded when I somehow managed to acquire a mate (of the female persuasion, no less).  She was OK with the arsenal (in fact she shoots better than I do), but not so sure about the other stuff.  I remember her reaction upon examining my survival food cache under the futon-- "Creamed corn? Seriously?" She shook her head.  "Bad survivalist."  It soon became apparent that having such a woman at my side was far better than being capable of briefly irritating the attacking US Government with the entire contents of my gun safe. Now, when the End Of The World As We Know It (EOTWAWKI) comes, I'll just sit back and let Sweetie handle it.  

Being a semi-reformed survivalist I may appear normal to most people, but I still get paranoid tingles once in a while.  And lately I've been thinking about GPS.

I noticed recently that both of my GPS devices, a Garmin GPSmap 60CS and Blackberry Curve, were displaying a circle of uncertainty around my position at normal map scales. Most of the time  I can rely on the GPS to accurately place me 2 meters from the third blonde on the left at the beer barge, should that unlikely need ever arise. But for some reason Both units seemed unsure if I was off the launch ramp, or sitting atop the marina store. It was no huge deal, I mean I probably wasn't going to lose track of the lake, but it was anomalous behavior from devices I had always trusted. Being a software nerd, I started thinking about this-- Obviously, something was going on with the constellation if both independent units were suffering from reduced resolution.  In minutes the old here-come-the-invaders reflexes, long dormant, re-energized and sent me into DEFCON II and a half.  Fortunately Sweetie stepped in just in time to slap some sense into me ("there are no black helicopters jamming your blinkie, idiot"), but the damage was done:  How much can we rely on GPS?

I assume anyone reading this knows generally how GPS works.  Many of you probably know in great geeky detail how it works. Some of you think GPS stands for Gerbil Positioning System, and it's all run by furry rodents from the Mothership behind the moon. Bless your hearts. Have you considered that the GPS constellation is getting rather long of tooth? I know that the system has worked pretty well (especially for a government program), but the orbiting Gerbil Containers are starting to suffer from squeaky hamster wheels after two decades in outer space.  It's not like they're replacing them routinely. One big solar flare, and all of a sudden we might find ourselves unable to locate the nearest Starbucks. Or the Shoals of Lingering Death.

And let's not forget that our blond-triangulating capability exists at the indulgence of our friends at the Department Of Defense, through a mechanism called Selective Availability. The gummint can, whenever it wants, flip a switch in some secret underground location and instantly cause thousands of powerboaters to crash at high speed into docks, shorelines, and each other. Okay, they are already doing that.  But it'll be even worse when their blinkies fail.

 Given the current global situation, Mr. Semi-Paranoid Survivalist Lite refuses to discount the possibility that the military  might have to enable Selective Availability at any time to prevent the technology from being used against us, for example if some whackaloon in Berzerkistan decides to fire off a cruise missile at Washington.

So, given that we could experience a general GPS degradation, or even a mass failure that befuddles millions of glowing dots on LCD displays, what should we be doing to make sure that we won't become hopelessly lost when our GPS suddenly bricks on us?

I'm probably in good shape. I don't think I'll get hopelessly lost on my lake (if I do, that'll make a great blog post). But a lot of you make epic SCA-worthy voyages, and actually sail out of sight of land sometimes. Have you thought about what you would do if your GPS suddenly becomes inert? When I eventually venture beyond my little lake, I figure I'll take my plotting tools, charts, and maybe even my plastic sextant, just in case. Perhaps I'll even try navigating the old fashioned way, and use the GPS for a backup only. Charts are easy to stow-- they flatten nicely under cases of creamed corn and gunpowder.

And when that cruise missile comes at me, I'll probably still be on course for the beer barge, instead of sailing around in circles like my GPS-dependent fellows.

What's your plan?