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    Re: News Item on Over-reliance on GPS
    From: Peter Fogg
    Date: 2008 Nov 7, 09:33 +1100

    Frank you asked:
    First, may I ask, just for the sake of comparison, is your chronometer
    You may, Frank.  Have both kinds of watches, electronic and mechanical, and note that my recently acquired Casio promises a 10-year battery life (4-months with me now, and seems to have settled down to about a consistent 1.5sec/month gain.  If its not a chronometer its still a pretty good watch).
    I have often found people extolling the virtues of celestial
    navigation because it is immune to electrical outages who nonetheless carry
    only battery-powered watches. You've mentioned previously that you do a
    survey of the timepieces of everyone on board at the beginning of a passage,
    and that's a great idea. But do you consider yourself at risk if all
    timepieces are battery-powered?
    Risk of .. all their cells failing at much the same time?  Seems a .. remote risk?  The on-board survey, incidentally, is ongoing, so an idea is gained of individual watch error and, if the passage is long enough, rate of change.  So even if all the other timepieces onboard fail to proceed, plus we have no radio, the last one going should still give us fairly accurate time, after correction.  I should say that the assumed-to-be-correct time comes from the GPS ! 
    Lets say the GPS dies, or a difficult to track-down error develops with its antenna-mounting connection out on the rail (personally experienced) or the boat runs out the vast numbers of cells needed for portable GPS continuous operation  (did you realise that those gadjets have an inordinate appetite for difficult-to-replace-at-sea cells?).  The result is: no GPS.  Have experienced just that - no working GPS - on a well-found boat that was carrying 3 of the silly things, including a portable device.
    What actually happens, its been all to common on so many different boats I've sailed on, is that for a variety of reasons the sole (the floor of the cabin) becomes covered in water.  This is usually very bad news for the batteries that are typically stored beneath the sole.  No battery life usually means you can't get the diesel motor going, and in one fell swoop you are, for most practical purposes, transported back to the 19th century.  You'd better have a good supply of everything you need for a happy passage that doesn't rely on electronics, because from that point on there ain't any, subject to individual cell life and supply.
    We thought we were so clever in our little boat, as we had every reason to believe it didn't leak (fibreglass hull and cabin) plus a different motor configeration, without batteries beneath the sole.  We spent a long day once punching into waves, sailing upwind, and after 14 non-stop hours of that I went below for a rest, stepping into cold water in the dark as I reached the sole.  So climbed back up and shared this good news with Annick: 
    "Houston, we have a problem".
    It wasn't too serious, happily, and after I bailed out the boat the water only came back slowly.  So much for not leaking !  All the cabin windows plus the forward hatch were streaming only a little of the green water being regularly dumped on them.
    All boats leak, given enough encouragement.  What also happens often enough is that they get pooped, a wave hits from behind and a lot of that water goes below through the hatch, if careless sailors have left it open.
    Or you may have a problem with fuel.  Algae seems to thrive in diesel fuel, especially in practice onboard, despite the stuff added to discourage it, and when enough grows it clogs the supply line and stops the motor.  The end result may be the same: no electronics.
    Electonics? - wonderful wizardry.  Marvelous.  Fabulously clever gadgetry, that increases our quality of life hugely.
    Reliable?  Out at sea in a small boat?  In your dreams ...

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