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    Re: What do offshore recreational navigators really do?
    From: Henry Halboth
    Date: 2005 Jun 6, 13:50 -0400

    It can only be said that it takes quite a bit of discipline, not to
    mention responsibility, for one to adhere to a rigid schedule of sight
    taking if not obliged of necessity to do so. On extended voyages, when
    following a great circle track, frequent fixes were considered necessary,
    perhaps appropriate is a better term, to keep the vessel on track - thus
    mini zing fuel expenditure and time enroute, and I am talking about
    within a few miles of the track. It was quite customary for me to take an
    average of from 10 to 14 sights a day to accomplish this end -
    specifically 5-AM stars + 3-AM suns, crossed with the moon or venus if
    available + noon Latitude + 1-PM sun to check on speed, again crossed
    with the moon or venus if available + 5-PM stars. What others may or may
    not do is purely their business, but at one time both commercial and
    naval ships required performance. I am sure that otherwise, on a long
    passage without expected navigational hazards, the major portion of the
    passage could be made by DR, with but a few sights in preparation for
    landfall.
    
    
       Henry
    
    On Mon, 6 Jun 2005 08:18:38 -0700 Lu Abel  writes:
    > Henry Halboth noted the tradition of 0800, 1200 and 2000 position
    > reports to the captain of commercial and military ships, along with
    > a
    > tradition of a noon sun shot.  I'm 100 years ago one could also have
    > seen several sextants on the bridge wings of any such ship at dawn
    > and
    > dusk, trying to bring down as many bodies as possible to get a
    > perfect
    > "pinwheel" fix.
    >
    > These navigators had an awesome responsibility of keeping safe a
    > very
    > expensive ship with hundreds of people aboard, so I can certainly
    > understand their meticulous behavior.  They were also navigating
    > large
    > ships with long turning times and deep draft, so "whoops, there's a
    > hazard, hard alee" wasn't an option as it might be on a smaller
    > recreational craft
    >
    > A year ago or so someone told me (and, unfortunately, I don't recall
    > who
    > it was, so I can't go back for more details) that a recreational
    > sailing
    > magazine had polled recreational sailors who had made long offshore
    > passages (including quite a few circumnavigators).  Of those who
    > regularly used celestial, the vast majority reported that they
    > simply
    > took morning, noon-ish, and afternoon sun shots and advanced the
    > resultant LOPs.   No star shots, no fussing at dawn and dusk, just
    > the
    > sun.   While I didn't question my friend, I'd assume these folks
    > might
    > also take daytime moon shots.
    >
    > I suspect their theory was that in the middle of the ocean, knowing
    > position to a few dozen miles was more than enough.  I also note
    > that in
    > a bouncing small craft, taking a sight with any degree of accuracy
    > is
    > extremely difficult.
    >
    > Comments?  Especially from anyone on this list who has made long
    > offshore passages on a small craft?
    >
    
    
    

       
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