A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: John D. Howard
Date: 2019 Dec 20, 16:56 -0800
Thank you - Thank you !
You have explained something that has confused me for over 40 years: Why anyone would mess with the longitude scale when the latitude is one minute equal one mile. I have never used the look-up tables HO 229 nor HO 249 although I knew how they worked. The requirement that the LHA be a whole degree means your AP longitude will most likely be an odd number of minutes. DUH !
My flying was from the 1960s untill I retired in 2009 and (almost) always used Lambert conical charts where the minutes of latitude were always the same and the minutes of longtitude got smaller as you went north ( south ). When I started playing with cel-nav the plotting sheets were the same. When I would read instructions on making home-brew plotting sheets, most were the same - latitude scale constant, but some would say mark the bottom in equal divisions and then adjust the latitude minutes. Now I can make sence of why.