NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Parallel Sailing question
From: Peter Hakel
Date: 2019 Jul 31, 21:48 -0700
From: Peter Hakel
Date: 2019 Jul 31, 21:48 -0700
Jayson,
Following Frank’s reply I used sailings.xls and composite.xls spreadsheets from:
https://www.navigation-spreadsheets.com
Treating 80° S, 179° W as departure and 80° S, 179° E as destination I get a distance of just under 21 NM for both great circle and parallel sailing. Track = 270 (west) in both cases. Note: in composite.xls I entered the limiting parallel in cell B9 as -80.00000001 to make the math behind this spreadsheet go through.
This distance of 21 NM is computed as 120 (minutes of arc for the 2° change in longitude) multiplied by the cosine of -80° (latitude).
Peter Hakel
35° 53’ N
106° 19’ W
File:
File:
