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    Read1st.txt Silicon Sea
    From: Dan Hogan
    Date: 1997 Dec 29, 11:37 AM

    For the benifit of new list members interested in the Silicon Sea cruise.
    Below is the revised Read1st.txt.
    Dec. 29, 1997
    The Cruise of the Silicon Sea
    If you want to join us, do. The only requirement is enthusiasm and
    participation in the discussions.
    Obviously those doing their navigation the old fashioned way, working for
    it, will need an Almanac. This makes the essential tools, Almanac, Plotting
    tools, plotting sheet, and a Sight Reduction method. The dates for the
    problems will be concurrent with the Nautical Almanac. All other information
    will be lifted from charts and documents available to the working group.
    In order to save some time, and make it easier on me, the cruise will pick
    up where the old one left off, at Palma de Mallorca in the Mediterranean.
    The route is consistent with Pilot Charts for the time of year (although
    mine date from 1978).
    The Route:
    Palma de Mallorca-Isle Horadada Light(departure point)-a point at the
    entrance to the Strait of Sicily-Port Said-Transit the Suez Canal-Transit
    the Red Sea-Adan(planned stop)-Cape Lueewin-Bass Strait-Sydney,
    Australia(planned stop)-Cape Horn-Barbados-Boston(home port).
    Be aware this is the planned route, STUFF Happens.
    Newbies, Oldbies, In-between-be's and anyone just plane interested, join in.
    The only requirement is PARTICIPATE. If you don't know, ASK. That's why we
    are doing this.
    I recommend a Navigation Log Book, aka. Spiral Binder. To keep track of your
    doings. Believe me it can't be done 100% on a computer.
    Again the required tools:
        1) A pencil and ERASER.
        2) Something to draw straight lines with.
        3) Something to layout angles with.
        4) Something to use as a plotting sheet.
        5) Something to calculate trig. formulas with.
        6) Nautical Almanac for sight reductions and sun problems.
        7) A pair of dividers.
        8) For us lazy souls, a Computer Navigation Program of your choice.
    Below is Dan Hogan's QED plotting for the financially under-privileged.
    Blatantly stolen from Self Contained Celestial Navigation with H.O. 208,
    John S. Letcher, 1977, International Marine, ISBN 0-87742-082-3.
    Use lined paper, college ruled, Turn the paper 90d, so the lines are
    vertical. Ruled lines are used for longitude. Every sixth or twelfth lie is
    darkened to represent a whole degree of longitude. (depending on the scale
    Lines of latitude are added by construction starting with the lowest
    latitude desired. Whole degrees are 60 miles. From your lowest Latitude line
    at the most R/H longitude line, draw a line at an angle up from the
    Latitude of your lowest latitude line plus 0.5d(ie.: 28.5d). For ten miles
    to the vertical line use 6 lines; for 5 miles to the line use 12 vertical
    lines. Where the angled line crosses your 6th or 12th line swing an arc
    until it touches your R/H vertical longitude line. This is the point of the
    next latitude line. Draw a line perpendicular to the longitude across the
    page. Repeat the process with each higher latitude (29.5d), etc.
    The bottom angle line, where it crosses the intermediate vertical
    longitude lines, is the distance interval. 10 miles each line for 6 line
    spacing. 5 miles each line for 12 line spacing. This forms a handy scale of
    miles or minutes of latitude. The accuracy is within the tolerance of your
    #2 pencil point.
         These are minimal charts with not much more than a coast outline and
    a lat-long grid.  They are all derived from the Map Viewer program at Xerox
    PARC, http://pubweb.parc.xerox.map, with place names from assorted atlases
    and encyclopedias.  I don't have any access to the detailed information
    usually found in navigation charts and these might better be called
    "chartlettes".  They are still usefull for providing some geographic
    orientation for the Silicon Sea cruise and if printed can be used as
    plotting sheets.
          For plotting you will need a course plotter or some device for
    measuring angles.  Each chart has part of the latitude scale graduated for
    measuring distance.  You need to construct a scale for measuring longitude
    but this is easy to do using the method outlined in Bowditch in the
    emergency navigation section.  You can probably get an accuracy of about 2
    nautical miles.
    This version of the Silicon Sea cruise starts with Leg 10 in Mallorca, Spain.
    Leg 10 IS THE FIRST problem in this series.
         Leg 10 to Leg 23 Cover the Mediterranean Sea.
         Leg 24 to Leg 26 Cover the Suez Canal and Red Sea transit.
         Leg 27 to  ?     Cover the Indian Ocean passage
                          Cover rounding Australia to Sydney
                          Cover Sydney to Cape Horn
                          Cover Cape Horn to Boston Harbor
    The Silicon Sea archives consist of:
    	SSNAVCRZ.ZIP - the problems with the answers in a text file
    	SSCHARTS.ZIP - a series of chartletts developed by Wes Murfin
    	 POSPLOT.ZIP - a Windows Plotting Sheet printing program by Wes.
    These problems are intended as self learning excersises and for the
    enjoyment of armchair navigators. Each problem is complete in it self.
    Alhough the cruise legs are a sequencial East about circumnavigation bound
    for Boston via Mediterranean, Red Sea, Indian Ocean, Austarlia, So. Pacific
    Ocean, So. Atlantic Ocean to Boston.
    Certain conventions were adopted as the cruise progressed. Most due to the
    ASCII requirements of the Internet. Such as, Hs for hs and Knots used in
    the calculation of current drift and set. Others I adopted to reduce the
    time spent developing, calculating and proofing the problems. They are all
    open to discussion. Nothing is cast in concrete.
    In developing the programs errors (intentional and un-intential) creep in.
    Please use these as points of discussion and post all questions about the
    cruise to the NAVIGATION mail list.
    To subscribe send the following message, with no subject to:
    On the first line of the message body:
         subscribe navigation 
         Without the <> of course. And no signature.
    When the server problems at roninhouse.com are solved the Silicon Sea
    archives will be files be kept there. In the mean time if some one can
    volunteer an FTP site for the Silicon sea files it would be appreciated.
    Until then I'll try to send them to those who request the files from me.
    Dan Hogan WA6PBY		     Yacht GACHA
        West Covina, CA		     Catalina 27
        dhhogan@lightside.com	     San Pedro, CA
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