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    Re: DR vs EP vs MPP vs Fix vs Running fix
    From: Bill Allan
    Date: 2002 Feb 7, 22:26 -0500

    I haven't been faced with the choice of how I would "reckon" with known
    errors such as Gulf Stream currents etc.
    My boating has always been on the Great Lakes (no tides, no Gulf Stream etc.
    etc). I would probably still use traditional DR techniques (since I know
    what it represents) and use more than the usual amount of  sun lines to get
    lots of rfixes if I was in doubt about the suspected strength of the
    current. At 6 knots I can't see much of a problem.
    ----- Original Message -----
    From: "Jared Sherman" 
    Sent: Thursday, February 07, 2002 6:36 PM
    Subject: Re: DR vs EP vs MPP vs Fix vs Running fix
    > Chuck - and all-
    >  <"The DR position is only an approximate position because it does not
    > for the effect of leeway, current, >
    >  Is there anyone here who would "reckon" their position without attemping
    to factor in ALL known effects? If one is plotting a DR position while
    crossing the Gulf Stream, even without knowing the current, is there anyone
    who would not indicate *some* offset as a best guess of the current, since
    they approximate current direction and speed are almost certain to exist to
    some extent?
    > I ask this as a poll, not as an arguement. My understanding of DR, the
    good Mr. Bowditch aside, was that a navigator placed EVERYTHING he could
    into the DR position and that it was supposed to include all "guestimates"
    of where you actually were, not just ignoring the ones you couldn't specify
    to five decimal places.

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