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    Re: Dated Chart Datum
    From: Robert Eno
    Date: 2008 Nov 4, 01:47 -0500
    I can add a few comments to Bruce's observations: 
    When steaming up the Labrador Coast in 2003, I noted that many of the charts -- particularly those for the northern half of Labrador -- had a lot of blank white spaces and in other areas the following ominous notices:
    "Islands, rocks and reefs too numerous to chart."

    "CAUTION: The information shown on this chart is of a reconnaissance nature and mariners should exercise caution when navigating in these waters."

    My all time favourite was the chart for the very northern tip of Labrador in the McLelan Strait area. We had been bashing our way north for 12 long hours, hoping to get to Port Burwell that day, but we were getting hammered by a gale and by the katabatic winds howling down the Fjords. I'd had about enough of getting beat up so we started looking for someplace to hide. We could not find anything suitable and so decided to anchor in a place called Clark Harbour -- immediately south of McLelan Strait, but which had big red letters: CANCELLED written across it. Still, we headed in to the area and found a decent anchorage and some protection from the storm. As my father used to say: "better than a kick in the arse with a frozen boot".

    In many areas, because of the lack of detailed information on the charts, we were travelling more or less blind and relying heavily upon our radar, sounder and DR plots and tracks on the chart. GPS was useful but in that area, depths were our major concern.

    Interestingly, the chart we had for the Fogo Island area appeared to be quite dated. I am certain the information was over 100 years old.  Nevertheless, it held us in good stead.

    As for metric charts, I have a serious and passionate dislike of these and an equal dislike for those luminaries in Ottawa who decided to replace fathoms and feet with meters. I have never been able to wrap my head around the use of meters for measuring depths. In fact I was on a small vessel that ran aground because the skipper got confused over feet vs. meters. Most of the charts for my particular area are still in fathoms and feet -- (mostly because Ottawa is too damn tight-fisted to update our charts), as is my US-made sounder, so I intend to hang on to these. Metric tyrants be damned.



    ----- Original Message -----
    From: "bruce hamilton" <bruce.hamilton@shaw.ca>
    Sent: Tuesday, November 04, 2008 12:51 AM
    Subject: [NavList 6438] Dated Chart Datum

    > I still remember going over the charts when I made my first trip around
    > Newfoundland and seeing that the charts were annotated with, "as
    > surveyed by James Cook, 1775". There was no indication of any updates. 
    > The waters were deep enough that we slept well at night, but the Mate
    > told us of meeting with an unmarked sea mount on one arctic trip.
    > Apparently shoring up a steel hull with wood and canvas still does the
    > trick.
    > The work that Cook accomplished is quite amazing especially considering
    > the equipment of the day.  I just realized that I used to know the
    > markings of the lead line, but have forgotten them completely. Was seven
    > fathoms red bunting?
    >  I wonder how many of the world's charts are still quite out of date. I
    > read once of a volunteer program in the UK where mariners submit the
    > soundings from their own GPS linked sounders, and the chart makers use
    > that data to help improve the systems. Is that really happening or was
    > it just a plan?
    > Oh, a little note on situational awareness.  In the early eighty's, some
    > genius in our nation's capital decided that nautical charts should be
    > metric and for a while you could have charts with soundings in meters
    > and feet/fathoms, as they were not replaced all at one time. We never
    > had any groundings, but we certainly had a few unkind words to say about
    > our chart makers as we jumped back and forth from metric to nautical
    > soundings.  I used to do the chart updates from the Notice to Mariner's
    > and burn all the old charts when they were finally replaced.  I wish I
    > had kept them all. I could have quite a collection, and I still love
    > paper charts!
    > Keep a good watch.
    > Bruce Hamilton

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