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Have you tried using the method in the N.A. to which you refer? I may be
missing something but I don't see anywhere in the given formulas where
you input course and speed which would be necessary if the method was
allowing for advancing the LOPs to a common time.

gl


P H wrote:
> As John Karl writes in his book:
> "The Nautical Almanac gives an iterative procedure for calculating a
> fix from several intercepts and azimuths determined from their St.
> Hilaire sight reductions."
>
> I would add that this procedure does take the vessel motion (assumed
> to be constant during the round of observations) into account.  I am
> confident that I am simply restating a fact that is well-known among
> NavList members.  Also, I think it is not unreasonable to assume that
> the content of the Nautical Almanac reflects common (standard,
> recommended, accepted, etc.) practice.
>
>
> Peter Hakel
>
>
> ------------------------------------------------------------------------
> *From:* hch 
> *To:* NavList@fer3.com
> *Sent:* Tue, February 16, 2010 8:20:41 AM
> *Subject:* [NavList] Re: Advancing LOPs for precision fixes
>
> Gary,
>
> You said ... "It is common practice to ignore the movement of the ship
> during the time period needed to take a round of sights ...", and I
> am unable to dispute this assertion in the light of today's "it's good
> enough" approach to Celestial Navigation. I can, however, state in no
> uncertain terms that this was not the traditional approach - LOPs
> generated in a round of sights were always advanced or retarted to a
> common time, so long as the distance run between individual sights was
> measurable, if for no other reason than professional pride.
>
> Regards,
>
> Henry
>
>

   

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