A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Tom Sult
Date: 2010 Dec 10, 08:56 -0600
Thomas A. Sult, MD
On Dec 10, 2010, at 2:34, Andres Ruiz <email@example.com> wrote:
Systemic error can be dealt with by bisecting each angle formed by intersecting position lines.
If a triangle, and azimuths with a spread of less than 180 degrees, then the fix will be outside the triangle. The probability is 100%.
With an azimuth spread greater than 180 degrees, then the fix will be at the centre of the triangle. The probability is, again, 100%.
I think there is some misunderstanding about bisector method:
· One is bisecting the angle of the triangle
· an another is to use the bisector of the azimuths of each pair of LoP. Has the important property
that is free of systematic errors.
I think it would be interesting to see the results of various methods. But I must confess, I use "Mark I eyeball" to estimate best fit.
For the example CY3 in my previous e-mail the solution by the bisector of the azimuth is the same as in LS:
I am agree with Tom; one thing is the mathematical basis, very interesting of course, and another is the real world, where in practical navigation I take for the fix in a cooked hat, not a point, but a circle with a radius based in my experience and felling of the circumstances, is the blue, not the coast, where piloting techniques must be employed.