A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Greg Rudzinski
Date: 2020 Jul 1, 05:17 -0700
The modern Doniol all haversine method is an azimuth intercept method designed to calculate altitude using a four place natural haversine table (no logs or calculator). Azimuth is solved by the Ix graph. I find that a single page with natural haversines every 10' on one side and the Ix azimuth graph on the other is capable of nearly 1' precision doing mental interpolations on look ups. The whole thing can be folded and kept in any wallet. Combine this with a single page pub 249 table 4 sun long term almanac and you have a complete wallet system with surprising precision. Add this table to a Bris sextant for extremely compact precise CN capability.
For non electronic standard law of cosine CN I like using the Otis King slide rule and a single page of 10' four place natural cos and sin table to calculate altitude and a 6 inch pocket slide rule to calculate azimuth. This method was first proposed here on NavList by Francis Upchurch.