NavList:

---Peter 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.

---Tom wrote:

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.

Regards,
 --
Andrés Ruiz
Navigational Algorithms
http://sites.google.com/site/navigationalalgorithms/