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    Re: sextant without paper charts
    From: Jeremy C
    Date: 2008 Nov 13, 04:37 EST
    Bruce wrote:
    "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."
    In my ten years out here I've never seen such orders.  My captain dictates a position ever 30 minutes in "inland waters" which to him means bodies of water like the East China Sea.  While I believe it is absolutely prudent to fix position using multiple inputs (I am quite certain mates use radar range and/or bearings to fulfill this particular standing order), mates must also be very mindful of vessel traffic.  With a modern merchant bridge team consisting of a AB/helmsman and a Mate on watch, it can be very distracting shooting visual bearings and radar information then plotting them on a chart.  It is VERY easy to lose situational awareness and run over a fishing boat or come into close quarters with another vessel if your head is buried in the chart plotting LOP's or running calculations instead of looking out the window to see what is going on.
    My point is, while it is very important to know your position, it is equally important to be aware of other hazards to navigation.  There must be balance to manage the bridge correctly, and the PROPER use of electronic navigation devices such as GPS should augment and verify what visual, audio, and/or radar information is telling you about where your vessel is, and what other vessels may be doing.
    For my part, I routinely use visual and radar information both in navigation (turn bearings, parallel index lines, etc) and for traffic avoidance (bearing drift of targets, ARPA).  I certainly check my GPS to make sure I am close to my track line, and verify that information when I can.  I am very comfortable with my position when i am watch because i take into due regard all information that I can acquire from my bridge equipment and my own senses.  I even shoot stars in the open ocean to verify position, but you knew that already ;-) I certainly do not rely on GPS alone in navigation the 650 ft long ship I stand watch on.

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