NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: Position lines, crossing
From: Bill B
Date: 2006 Dec 12, 01:20 -0500
From: Bill B
Date: 2006 Dec 12, 01:20 -0500
Lu wrote: > The atmosphere, refraction, and even the > conductivity of the earth (influenced by things such as moisture > content) affects the speed of radio waves. Loran designers could > compensate for some of this with calculations, but effects caused by > things such as ground moisture required experimental measurement. > Without knowing these systematic errors, Loran had great repeatability > (coming back to an exact set of Loran coordinates would typically bring > one to within � 50 feet of the position where they were originally > measured) but initially poor absolute accuracy (L/Lo as calculated by > the box and/or from TD LOPs plotted on charts) (typically 1/4 mile or > more). If I recall older texts, Loran radio waves could also be subject a change in direction/speed by to bouncing off bluffs, cliffs, and other land obstacles. Is that fact? Bill --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to NavList@fer3.com To , send email to NavList-@fer3.com -~----------~----~----~----~------~----~------~--~---
