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H Bill and Peter, yes some of us are still working SS!! Via my SS
notes Dan Hogan's email(s): dhhogan@concentric.net
and
dhhogan@earthlink.com. West Covina, CA, is Dan's residence very close
to mine. HTH.
Mike Burkes
626-833-1521

On Jun 9, 10:18�am, wjlub...@yahoo.com wrote:
> Two months ago while while surfing the net looking for information to 
supplement my books on navigation, I found this site and the very useful 
downloads available on it. The Silicon Sea problem was just my thing. I am 
impressed with the amount of research, work and effort that went into 
creating it.
> �
> Us landlubber arm-chair navigators seldom get to breath the salt air or feel 
the green water spray over the bow. This at least gave us the opportunity to 
remember it. Ten years after you created this adventure, my cruise left�Palma 
de Mallorca.�I have been working the legs and now find myself ready to leave 
Rio de Janerio and start leg 61.
>
> �
> A couple questions, yes I have many!
> (1) Often wind force is listed. It is stated as: "Wind is force 4 from 175 
degrees." I have been multiplying the average speed in knots by a factor 
(0.02) to get the current drift and rotating the direction for Coriolis by 30 
to 45 degrees when the latitude is at least 30 degrees from the equator. Is 
this the intent of the problem? Or, should I just be using the given wind 
direction as the set?
> �
> (2) Often current set and drift are given. Is it your intent that this be 
included with course and boat speed as a known condition in the computation 
of a DR position. In the notes, it stipulates that only estimated position 
(EP) should include DR+current effects. I have seen it done both ways.
> �
> Is their any errata out their for the legs or answer sheets? I have run 
across what appears to be typos in the on-line material. The answer sheets 
are great as they really make you work to get the listed answers. �
> I have had my share of problems and misunderstandings of the instructions 
but have persevered. Needless to say, I have had to do a lot of review and 
learning especially of the sailings. My answers do not necessarily correspond 
to those given in the answer sheets but most are close. I would like to share 
them with any one interested. No guarantee that my answers are�correct. 
Converting zone time to universal time and back over several time zones has 
been a challenge.
> �
> My methods of solution:
> Celestial observation:
> For most legs, I have used HO229 and Ageton for astronomical position with 
backup from a HO214 program on my HP34C pocket calculator and Omar Reis's 
Navigator program which I have a registered copy. Plotting is done with 
plotting sheets downloaded from the Navigation -L site.
> �
> The sailings:
> Rhumb line navigation is done with mid-latitude sailing or Mercator sailing 
with backup from a Rhumb line program on my HP35S. Great circle sailing is 
done with Ageton's tables or calculation,�with�backup from a great circle 
program on the HP35S.
> �
> Questions involving current set and drift, true course to steer, cc/CTS�etc.:
> Solution has been by calculation�or graphically�with maneuvering board 
sheets downloaded from the Navigation-L site.
> �
> I understand that using a pocket calculator or worse a computer is 
disgusting, or at least probably not reliable at sea, but they are great 
checks on the work.
> �
> I have been reading a lot about slide rules�in the forum. I own a Post 
Versalog�(Log Log Decitrig, 23 scales)�slide rule, which I made my living 
with for 15 years. I put it on the shelf after buying my first HP calculator, 
an HP 45 in 1974-75. It did polar to rectangular coordinate conversion which 
saved a lot of time. I still use the Versalog occasionally just for fun. It's 
as accurate and readable today as the day I bought it in 1957. The Versalog 
had a magnifier but it has long since disappeared. Most work we did in those 
days, away from our desk,�was done with a 6" plastic (often cracked) slide 
rule some vendor gave us. It worked fine before the pocket calculator became 
available. Enough on slide rules.
> �
> Thanks guys, looking forward to hearing from you.�
> �
> Bill Lubitz
> �
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