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    Re: sextant without paper charts
    From: Henry Halboth
    Date: 2008 Oct 31, 20:01 -0700

    It may be of interest to some to note the following excerpt from "USCG Safety 
    Alert HMRMS04-7", regarding Navigation in restricted visibility, as issued by 
    Sector Hampton Roads on December 13, 2007, particularly the apparent time 
    delay for a track line to upedate on an electronic chart.
    It seems that such a time delay could have rather far reaching implications.
    Excerpt ...
    "TAKE FREQUENT POSITION FIXES. Too often mariners fail to appreciate the 
    importance of frequent fixes while navigating in restricted visibility. Over 
    reliance on radar and electronic navigation systems can cause a mariner to 
    lose situational awareness, in part because of time delays while the image is 
    refreshed. A vessel can travel several hundred yards, especially if the 
    operator fails to reduce speed, in the time it takes for the track line to 
    update on an electronic chart. In some cases it may be necessary to take 
    fixes as often as every three minutes."
    --- On Fri, 10/31/08, bruce hamilton  wrote:
    > From: bruce hamilton 
    > Subject: [NavList 6407] Re: sextant without paper charts
    > To: NavList@fer3.com
    > Date: Friday, October 31, 2008, 9:13 PM
    > Navigation without paper charts probably contributed the the
    > sinking of
    > The Queen of the North here in British Columbia. It ran
    > aground because
    > the bridge crew did not know where they were, and they were
    > in
    > restricted waters in a 3 mile channel.  Can any of you even
    > imagine
    > being so out of touch!  I doubt it.  I have seen very drunk
    > Captains
    > with much more sense than that.
    > Without having to plot fixes every 15 minutes there is a
    > tendency for
    > bridge crew to rely solely on the information on the screen
    > and not be
    > aware of where they actually are.  I have a friend who is a
    > merchant
    > captain who still has standing orders for the mates plot a
    > position on
    > the paper chart every 15 minutes by some method other than
    > GPS.   If you
    > are in within a few miles of land, then then this is really
    > essential in
    > a big ship. Our eyes and brains are the best navigational
    > tools that we
    > possess, and the they don't even require electricity.
    >  I spent 2 years on 730 foot freighters going through the
    > great lakes.
    > If any of you have ever been through the St. Lawrence
    > Seaway on a boat,
    > just try to imagine what it is like on a ship. The mates
    > and masters who
    > do the piloting just know where they are by looking out the
    > windows.
    > One comany pilot I worked with used to show me how to do
    > the river
    > without the buoys using only natural landmarks. Quite
    > impressive. There
    > is no doubt that GPS is a great aid and saves countless
    > hours on the
    > hook waiting for the fog to clear out of such places as the
    > American
    > Narrows.  I had a captain who ran a ship around there in
    > the pre-GPS
    > days.  He was half way through and the fog came in. The new
    > short range
    > radar had too much clutter to see properly so he had to
    > guess about when
    > to make a turn. He had been trying to get the radar fixed
    > for several
    > weeks, but the office thought it was OK to run without it.
    > There is
    > never any bad weather or fog in the office  is there! :-)
    > In that case,
    > the GPS would have prevented the accident.
    > Keep a good watch.
    > Bruce Hamilton
    > Vancouver, BC.
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