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    Re: Leg 55 results
    From: Dan Hogan
    Date: 1999 Jun 21, 12:11 EDT

    >Here are partial results from Leg 55:
    >1.  Mar 16 2101Z DR = 47 20 S 122 52 W
    OK Lat a tad off on Lon
    >2.  To 52 30 S 100 00 W, TC = 109, dist = 930 nm
    Very Close in TC. nm oof per Lon
    >3.  Compass course = 82, speed made good (not asked) 10.8
    Very close same diff as Q2.
    >4.  Mar 17 0520Z fix, all over the ocean.  My 0520 DR is 47 42 S 121
    >20 W.  I reduced all 5 sights, and the LOPs are everywhere!  Some of
    >the intercepts are more than 2 deg.
    Just pick 3 sights that are spread apart as close to 90 degrees as you
    >Conditions here are not the best.  Since I don't have the 1999
    >Almanac, I'm following the instructions for using last year's edition
    >(deduct 15.1' from GHA Aries).  Also, I don't have an HO 229 for this
    >latitude, so I'm using the reduction tables in the Almanac.  Between being
    >rusty and using unfamiliar procedures, probably have made some blunders.
    >body            time     GHA    aLon  LHA      dec     Hc   Zn
    >Betelgeuse  02:50:00  127 58  120 58    7   N 7 24  34 16  351
    >Procyon     02:51:10  102 13  121 13  341   N 5 14  34 14   23
    >Peacock     02:51:24  270 43  121 43  149   S56 44  17 52  197
    >Regulus     02:52:22   65 15  121 15  304   N11 58  12 15   56
    >Bellatrix   02:53:11  136 16  121 16   15   N 6 21  34 04  342
    If you have WEB access got to the Navigation-L page
    (http://nav.cnchost.com) and down load ALMNAC20.ZIP. It is free ware
    and will provide sufficient accuracy for Silicon Sea.
    >All plotting was done on sheets of typing paper.  DR computations by
    >E6-B air navigation slide rule.  Sight reduction by paper and pencil. By
    >the way, keeping up with Silicon Sea with traditional methods is pretty
    >time-consuming, which is the main reason I don't always participate.  I've
    >noticed everyone else seems to use computers.
    POSPLOT.EXE is a freeware program to print plotting sheets on 8.5x11
    paper. I have used it on Laserjet and Deskjet printers. On the boat I
    use the Q.E.D. plotting sheet.
    There are several freeware and Shareware Sight Reduction programs
    available at the Navigation-L Web site. I use NAVIG94, shareware, for
    the Silicon Sea on the computer.
    >I may go back to HO 211 for reductions.  The thing I like about 211 is
    >that you don't have to contrive an "assumed position" which is miles from
    >your DR, and different for each sight.  You simply use your DR for the AP.
    > The computation is more involved than HO 229 or the NAO tables, but you
    >get some time back from the simplified plotting. Plus, as soon as you
    >compute the intercept you get instant feedback on the agreement between
    >the LOP and your DR.
    When I first started in navigation I used 211, but I was prone to
    making mistakes with it. I used H.O. 208 and reached a point where I
    could reduce a FIX within five minutes. The inspection tables (249 &
    229) are faster. I currently use a pair of HP 32SII calculators, one
    for Mercator Sailing DR and one for Sight Reduction.
    Dan Hogan WA6PBY
    Navigation-L: http://nav.cnchost.com

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