NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Herman Zevering
Date: 2010 Mar 1, 19:45 -0800
Well done Lars Bergman! This is the only way to advance the argument, mathematically. I must admit I hadn't thought about the issue from this particular angle. There still seem to be a few difficulties with it, but nothing major. A very minor one is that the formulas you use technically only compute calculated altitude (Hc). Thus, Alt1, Alt2 are not the same as observed altitude (Ho). But you can always assume to simplify the argument that the DR positions (Lat1/Long1 and Lat2/Long2) happen to lie exactly on the position circles. It makes no difference to the crux of your propositions. In other words, just assume that the intercepts are zero, right?
Perhaps an unintended problem is that eq.(4)as it stands is merely a restatement of eq.(1). This is simply because Lat2-d'Lat = Lat1 and Long2-d'Long = Long1. So eq.(4)does not as yet represent a transferred position line but the same original position line, if you know what I mean. This of course affects the conclusions you draw from equating eq.(1) and eq.(4'). So QED is still in a sense 'quod est non demonstrandum'.
But despite these obvious teething problems of your model, I nonetheless think that the methodology is interesting and worth pursuing. Also George Huxtable apparently thinks so You are evidently casting about for a simple Intercept Method formula that defines the position line transferred with RFT (the running fix technique known from coastal navigation which George maintains is applicable to celestial navigation and I maintain it is not). You perhaps intended to substitute the coordinates of DR2 into eq.(1), the negative signs perhaps intended as being positive, e.g Lat2 = Lat1 + d'Lat etc.)?? I just voice some queries on this.
But what I have pointed out above by no means detracts from the cogency of the principle of your demonstration, which could well be the key to breaking the deadlock on RFT versus GD-UT once and for all. So please take my comments as being merely constructive. My quixotic attempts to defend my position on the issue and George's veritable crusade to keep the traditional banner of RFT flying at all cost, of course didn't get the argument any farther (we both still think we are right). So a fresh approach to the issue based on the kind of mathematics you have in mind should certainly be applauded, like George has already done. And of course it should be fully covered in NAVLIST. Cheerio. Herman Zevering.
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