NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Lars Bergman
Date: 2025 Oct 7, 03:30 -0700
Further to my previous post, I think Vincenty's formula calculates the distances along the curved surface of the earth, or rather the reference ellipsoid. Enclosed is an Excel file that calculates the straight-line distance between Frank's towers. I have assumed a tower height of 10 m and added an approximate altitude of the island that I found somewhere on the net. The higher up you are situated, the longer the distance between the different points. However, the differences seem to be less than one decimeter in this case.
Perhaps someone wonder why I wrote artanh instead of arctanh. According to my teacher many years ago, the hyperbolic functions are related to area rather than arc, hence the c should be omitted. Excel does not follow this standard.
My remark on the closeness between WGS84 and the actual earth may perhaps be irrelevant, as the positions were based on GPS. I guess those positions are somehow reduced to the WGS84 ellipsoid, but I may be wrong.
Lars
