A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Samuel L
Date: 2015 Nov 26, 05:40 -0800
I had solved the problem before anyone replied to this topic and Chapter 24 was only somewhat helpful in the solution. And to be blunt and forthright- at my age I don't have the time to fiddle around with concepts and theories- I want the method that'll provide the result.
The equations I used have since been discarded and replaced with Peter's formulas in the PDF he sent. Both the equations I used (Hc & Azimuth) and Peter's produced the same result- his are less lengthy.
I'm trying to stay away from using spreadsheets (computers) to solve these sort of problems because, when sailing, battery power is needed for computers. (Dead batteries and I go hand in hand). An "app" on a tablet, or just having a tablet, on board a boat for me is a recipe for disaster.
The other fellas' interest in the Bygrave is fascinating- a solution without any electricity needed. For me, less electronics is better. A calculator can provide an answer, in this case, faster than a computer. Plus, I just enjoy working with paper, pencil and often a calculator. Today, there is simply and overdependence upon electronics.
I can see that you will be getting more confused by the minute. You might want to download Bowditch Chapter 24: The Sailings here.
2411. The Traverse Table and 2415. Middle-Latitude Sailing, might shed some light on your problem, as they apply to plane trig over relatively short distances on the earth's surface, where the rhumb line rules.
The chapter also contains the spherical trig used in great circle nav - a bit more complicated.
Best of luck and apologies if this does not help at all.