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    Re: Newbie - Variation Question
    From: Pierre Boucher
    Date: 2002 Feb 11, 11:02 -0500

    Hi Andrew,
    That is the way the french deal with variation (declinaison)
    The basic formula being:
    True + Variation = Magnetic
    They consider :
    West variation as positive and
    East variation as negative
    So the negative East variation is added to True to get the Magnetic.
    Hope this help,
    Pierre Boucher
    >I realise the list is for non electronic navigation methods but I need some
    >confirmation on an issue of magnetic variation.
    >I recently purchased a hand held GPS to back up my celestial on my first
    >offshore trip (solo).  Whilst I was familiarising myself with the unit the
    >other day, I found after much head scratching that the unit actually ADDS
    >easterly variation to true to get a magnetic heading readout.
    >I was always taught that "variation east, magnetic least" - all my
    >navigation text books including Bowditch back this up.
    >I contacted the Australian importer of the GPS this morning who said they
    >had been aware of the problem for 18 months, had taken the issue up with MLR
    >France ( the manufacturer)
    >and were advised that it was the way that the French deal with variation( ie
    >add rather than subtract Easterly variation to get magnetic course).  The
    >importer said they were happy with this explanation.
    >Anyway, I just wanted to confirm that the world over that Easterly variation
    >is subtracted from true to get magnetic.  If it isn't, well at least I've
    >learned something today.
    >Thanks in advance.
                  XX X                                 Pierre Boucher N
                XXX XX               formation en navigation de plaisance
              XXXX XXX                 Ste-Therese (Quebec) Canada
            XXXXX XXX
          XXXXXX XXX          la "VOILE"...  le reste n'est que du vent...
      XXXXXXXXXXXXXX       ''Sail, Sail !''... the rest is only wind
                XXXX                      EMAIL: pboucher@lavoile.com
                XXX                               "http://www.lavoile.com"

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