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>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
can.
>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
dhhogan@XXX.XXX
Navigation-L: http://nav.cnchost.com

   

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