A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Gary LaPook
Date: 2020 Mar 18, 00:36 -0700
Your final result is only as accurate as your least accurate input. Since HO 249 only provides data to the integer minute it make no sense to combine it with the more precise HO to a tenth of a minute. Just round the HO to the nearest minute, combine with HC and plot the intercept to the whole nautical mile (minute of arc.) If you want more precision in your celnav then you need a more precise method of sight reduction, HO 229; HO 214; HO 208; HO 211; or various computer apps.