NavList:
A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Re: AP terminology, WAS: 2-Body Fix -- take three
From: Peter Fogg
Date: 2009 Nov 12, 14:13 +1100
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From: Peter Fogg
Date: 2009 Nov 12, 14:13 +1100
John Karl wrote:
Ahhhh Frank, see what I mean----
All these posts, and look at the confusion: The DR is an AP, it's one
particular choice of an AP. And tables have nothing to do with it.
Beg to differ, John. To start with, where is the confusion we should be looking at? I don't see it.
Next, the AP involves an artificially assumed position for the convenience of some tables entry, much as Jim has explained (without succeeding in confusing me - your mileage may vary). Adopting the DR involves use of the best estimate of position with the intercept method. Different.
Only by trying to merge these different positions into one, as per your: "The DR is an AP" could confusion be created, which might be one good reason so not to do.
Has anyone answered the question WHY we use an AP in the intercept
method??
Could Jim have already done so? For convenience of some tables entry?
To phrase it another way, since we know everything needed to
calculate the celestial LOP (the GP's location and the altitude), why
not just calculate the LOP directly?
We're tuned in and awaiting the answer with bated breath, John. The floor is yours..
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