NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: David Pike
Date: 2024 Sep 30, 05:18 -0700
ThomasK
Please see below my reduction using the Nautical Almanac. Against my better judgement, I decided to try the Concise Reduction Tables for the first time ever. These, I eventually realised, work by splitting the celestial triangle into two right celestial triangles. Three hours later I’d re-christened them Brain Reduction Tables, because mine felt as if it had shrunk to the size of a two-year-old walnut. Zn was coming out fine, but I couldn’t make Hc give me a PL anywhere near that found in my earlier work using HO249/AP3270. Therefore, I had to revert to the spherical cosine law, which at 81 in November is tantamount to age abuse. That seemed to work OK and came within the thickness of a 2B pencil of the Air Almanac Method. I’m determined to get these Concise Reduction Tables working for me, but for the moment, I need to give them a rest. I might even try using one of the apps stored on my phone, which I keep forgetting I've got, as a referee. DaveP
