NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Fix from 2 Bearings
From: UNK
Date: 2003 Jul 11, 11:30 -0400
From: UNK
Date: 2003 Jul 11, 11:30 -0400
On Friday, July 11, 2003 10:43 AM Dan Allenasked: ... > I sighted Mount Baker at 50 degrees east of North. > I sighted Mount Rainier at 140 degrees east of North. > The compass was uncorrected for magnetic deviation for these readings. > From http://www.ngdc.noaa.gov/cgi-bin/seg/gmag/fldsnth2.pl the magnetic > deviation for this location and date is 18d 47m East. > >CHALLENGE: > >Determine the point of observation! I assume that we are to apply the correction for deviation ourselves... My FIX was at 48d 32.3'N 122d 44.0'W I used a spreadsheet I wrote that solves a two-LOP fix using rhumb lines determined by mid-latitude. I'm betting that the solution using great circles differs by no more than 0.1'.