NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Mileage of rhumb line compared to mileage of great circle
From: Peter Hakel
Date: 2011 Jun 4, 11:52 -0700
From: Peter Hakel
Date: 2011 Jun 4, 11:52 -0700
Here are the differences between rhumb-line and great-circle distances for the first example in Gary's "additional mileage" table compared with calculations in the attached screenshot:
Example 1: Singapore to Cairo
spherical: 28
ellipsoidal: 48
table: 29
The difference in initial bearings is 8 degrees (301 for the great circle; 293 for the rhumb line) both by computation and by Gary's "conversion angle" table.
The effect of Earth's flattening on the distance (as described e.g. in Andres's paper) is smaller for the great circle route and more substantial for the rhumb line.
Peter Hakel
Example 1: Singapore to Cairo
spherical: 28
ellipsoidal: 48
table: 29
The difference in initial bearings is 8 degrees (301 for the great circle; 293 for the rhumb line) both by computation and by Gary's "conversion angle" table.
The effect of Earth's flattening on the distance (as described e.g. in Andres's paper) is smaller for the great circle route and more substantial for the rhumb line.
Peter Hakel
File:
