# NavList:

## A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding

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Observing Celestial bodies
From: Byron Franklin
Date: 2013 Mar 19, 17:31 -0700

Byron: A person who understands the nature of errors avoids many pitfalls. Thus the magnitude of the error of individual lines of position is not a reliable indication of the size of the error of the fix
obtain from them. The size of the triangle formed by three lines of position has often been used as a guide to the accuracy of the fix, although a large triangle might be the result of a large constant error if the objects observed are equally spaced in azimuth. On the other hand, two lines of position with small errors might produce a fix having mach larger errors if the line crosses at a small angle.”Bowditch.
Byron “Let us use a large angle nearest to 90 degrees for accuracy for the best fix”
What I have seen and read in the course books on Navigation is bad for the beginner.
The real needed information is not complete, sure you can get the job done using what is in the books,
but if you want to get the best fix you must understand how to think, the books won’t help.
In my Franklin Piloting Technique the navigator takes 3 Navaids two Navaids are selected for the fix. In this case the two closer Navaid become the ships position. The farthest Navaid become an indicator of accuracy and can give a direction + or – and the amount of error in degrees the Navigator can solve compass error and get the good fix. It has been taught at navy schools including the Naval Academy as well the Navigation Bowditch and Chief Quartermaster Manuel.
Taking a celestial round of stars has some similarity in that a round of sights with near to ninety degrees cannot be improved upon as far as the angle of cut, but you must have an indicator as to accuracy, the same as the piloting technique. You must add another star or more. They will not improve the fix position, but can give a clue to the accuracy. If they do not support the near 90 degree best fix, chose the next best near 90 intersection. Often you will see an example in the book of three stars one with East –West Line of position No. two with a 045-225 No 3 with 000-180 and the fix in the center of the three. The 90 degree position should be the best choice. The present books will pick the center of the three lines as the idea choice! This is alright, I will not argue about this, but for myself I will pick the best intersection near 90 degree as my fix. I will be correct more times than the book. We are nit picking, but my experience on board a Radar Picket Liberty Hull for 5 years using sextant and loran A for fixes while tracking aircraft coming to the US shore. I had to get ships positions by sun-lines and shooting stars for l fixes for reference tracking point at sea I had 27 years of at sea Navigation and Navigation teaching at Naval schools
My third ship a Liberty Hull with it old bad equipment and lack of on board knowledge taught me well.
The encluded is from my old Navy QM book on Navigation.
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