NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: UNK
Date: 2014 Jan 29, 06:54 -0800
Hello Randy
You have already solved your problem with NASR: You missed a sign reversing rule. My comments are therefore a little late.
I too find it interesting to try different reduction methods. I too have had difficulties with all “special rules” in methods like Aquino, Dreisenstok, Ageton and NASR.
I suppose that’s why the cosine-haversine method could prevail for so long time. In spite you have to add five or six digits logs when using it.
Attached are, for your interest and others (?), six methods I have used solving your Capella sight.
1) NASR
Printed on the form published in the almanac.
The printed answers are given by my machine.
2-6 are my “personal” excel forms.
Here too the answers are produced by my machine.
I use empty versions and pencil (and rubber) for my manual, “longhand” exercises.
2) NASR
My form with the same reduction answers as in 1.
3) HO249 vol2&3
This is a fake! Vol2&3 can’t be used with declinations over 29°. Nevertheless, my machine ignores that and gives correct “HO249 vol2&3 values” – can be checked with HO229 (Hc 55°16,7’ d -3,5’ Z 57,9°), decimals rounded off.
4) Cosine-haversine and abc-tables
Whole minutes and five digits logs.
5) Ageton
Half minutes and five digits.
6) Time Sight
¼ minutes and six digits logs.
The longitude calculation isn’t necessary. It is easy to choose hour angle and longitude without it.
Finally: A warning.
I am neither a celestial nor an excel expert.
Don’t trust me and my machine too much.
Paul Werner
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