
NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Which Method do you prefer using and why.
From: Robert Eno
Date: 2013 Apr 4, 20:40 -0400
From: Robert Eno
Date: 2013 Apr 4, 20:40 -0400
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Good points Lu.
As indicated in a previous note, I prefer an
electronic calculator using the spherical trig formulas. I have a solar-powered
Texas instruments scientific calculator that I purchased in 1988. It has been
with me at sea, in the arctic and all points between. And it has never failed
me.
To keep my foot in the past and (as I indicated in
my earlier comments) to keep my mind sharp, I used the spherical trig formulas
coupled with set of trig and log tables. Pretty basic stuff.
I do, however, disagree with you on the utility of
the NA concise tables for reasons already iterated in a previous post.
Robert
----- Original Message -----From: Lu AbelSent: Thursday, April 04, 2013 5:30 PMSubject: [NavList] Re: Which Method do you prefer using and why.
Stan, you've inspired some clarity for me.
It seems to me there are a variety of people who are on this list:
1. People who want to learn celestial. A goodly subset of them are probably "want to learn celestial as a backup to GPS for offshore voyaging."
2. People who want to learn (or learn about) historical techniques -- everything from lunars to how Captain Cook might have navigated.
3. People who don't trust anything with electronics inside it.
What sometimes bothers me is when people don't make it clear what camp they belong to (or maybe they're not even in touch). Having cut my celestial teeth on HO229, I can't put myself in the camp that says it's faster than Law of Cosines on a calculator.
But my major point is to hope that if people want to talk about celestial navigation in the 21st century they will be practical about it. If I were to go offshore in a private boat (ie, not a 1000' ship) how much space and weight (and money) is it practical to devote to navigational gear? Would I want to carry four heavy, bulky volumes of HO229? If so, why? Would I want the bulk of Bygrave slide rules or would a calculator suffice? Why? Etc, etc, etc.
Maybe because I am a US Power Squadrons member and have taught their celestial courses, I agree with their view of offshore navigation for the 21st century -- (1) celestial is a backup to GPS, and (2) the Nautical Almanac sight reduction tables are a good backup to LOC/calculator reductions because they're in the NA and therefore you don't have to carry anything extra.
Lu
From: Stan K <slk1000---com>
To: luabel---com
Sent: Thursday, April 4, 2013 1:45 PM
Subject: [NavList] Re: Which Method do you prefer using and why.
Geoffrey,The NAO tables are one of the only two methods currently taught by the United States Power Squadrons (USPS), the other being the Law of Cosines "calculator" method.The Power Squadrons has been trying to make their courses more practical, admitting that GPS has replaced celestial as the primary offshore positioning method. However, they still support celestial as a backup and as a method of checking your GPS. With that in mind, they decided that NAO would be the only tabular method taught, since it is contained in the one book you are required to have anyway, the Nautical Almanac.This makes some sense, until you consider why people take the two courses that still included celestial navigation, Junior Navigator and Navigator. Informal surveys have shown that only 10% of those taking the courses ever expect to use what they learned offshore (and only a small percentage of those actually do). People take thes courses because they are interested in the material. They want to understand what was cone in the historical novel they just read. They want to learn about the things that they use every day and never give a second thought. An example I use in class is the times of sunrise and sunset announced on the radio - how much does it matter exactly where you are?Several of us involved in the USPS courses would like to see some of what has been removed from the courses (e.g. there is no mention of the Equation of Time) put back, but we may be fighting a losing battle. One thing being considered is putting the removed material into a supplemental program. Time will tell.Stan-----Original Message-----
From: Geoffrey Kolbe <geoffreykolbe---com>
To: slk1000 <slk1000---com>
Sent: Thu, Apr 4, 2013 1:04 am
Subject: [NavList] Re: Which Method do you prefer using and why.
Is there anybody out there, anybody at all, who uses the NAO tables in the back of the Nautical Almanac (and also in the back of the 2nd edition of my LTA)
Geoffrey KolbeView and reply to this message: http://fer3.com/arc/m2.aspx?i=123312View and reply to this message: http://fer3.com/arc/m2.aspx?i=123333View and reply to this message: http://fer3.com/arc/m2.aspx?i=123334
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