NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Just getting started
From: David F. McCune
Date: 2007 Jan 18, 00:37 -0800
From: David F. McCune
Date: 2007 Jan 18, 00:37 -0800
Gary: Welcome to the list and to celestial navigation. I am an avid long-distance solo sailor and use celnav as my primary (indeed my only) offshore navigation method. (I am trying to be the last sailor on earth not to have a GPS on my boat.) Let me assure you that I am neither a math wiz nor an astro physicist! And I learned from "A Star to Steer Her By." The arithmetic is intimidating to most beginners. Assuming for the moment that you use sight reduction tables, then all there is is VERY simple arithmetic. Trust me, I am mathematically challenged. I couldn't explain trigonometry to you if my life depended on it. But that's just my point. My life HAS depended on my celnav skills any number of times, and though I am a mathematical idiot, I am still alive. There are really only five basic steps: (1) Figure out the exact GMT of the sight; (2) figure out the LHA and declination of the body at that time; (3) figure out the actual corrected angle of the body you saw through the sextant; (4) look up in the tables the computed angle to that body at your assumed position; and (5) plot the line of position based on the angles and azimuths you figured out in (4) and (5). I have reduced thousands of sights over the years. I can do it on the back of an envelope in less than five minutes. The hard part isn't the sight reduction, even though it feels that way to a beginner. The hard part is hanging on a tether on the deck of a small sailboat in 20-ft seas and getting some celestial body to line up with some approximation of a horizon. The rewards are immense. I can remember like it was yesterday the first time I sailed alone to Hawaii with only a sextant, a watch, a nautical almanac and H.O. 249 for navigation. Mauna Kea appeared over the horizon when and where I thought it would. I felt like I had cracked God's own secret code in finding my way there. My advice to beginners is just to learn the basics at first. Use one of the simple sight reduction methods and one of the workforms, such as the Davis workform. Basically you need to learn to find your way around the Nautical Almanac and the sight reduction tables. Once you've done that a few dozen times, your natural curiosity will have you trying to understand WHY it all works. There was a time not long ago (say 20 years) when every small boat sailor who crossed an ocean had to learn cel nav. Those of us who did just wanted to make it as easy and as foolproof as possible. Cel nav was just a necessary tool for the voyage, like knowing how to bleed a diesel or tie a bowline. I'm grateful to the experts who invented the tables and almanacs I use. When I'm hunkered down in my nav station after twilight, heeled at 20 degrees, braced against the thudding of the waves and squinting under the red night lights, I'm not interested in trigonometry. I just want an answer to the ancient question of all mariners: where am I? Anyway, I hope you can manage to keep your studies simple for now. Learn the mechanics and the most very basic theory. It's not hard and requires only a bit of perseverance. Once you've done that, you'll be proud of yourself. And if you're like me, you'll want to learn a lot more. Which is where this list comes in. The members here know more about celestial navigation than I ever will. There is not a question about cel nav that I can imagine asking that someone here wouldn't know the answer to. Good luck and don't forget to get out on your boat and use your sextant! David --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---