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Subject: Re: Variation of compass
From: David Weilacher (daveweilacher@XXX.XXX)
Date: Thu Oct 03 2002 - 13:38:12 EDT
Actually it was intuitively obvious to the most casual observer; right after
I'd pressed the send button.
On Thu, 3 Oct 2002 13:25:22 -0400 Michael Wescott <wescott_mike@XXX.XXX>
wrote:
> daveweilacher@XXX.XXX said:
> > One thing I attempted was to compute compass
> variation by assuming a
> > GP for the mag north pole of 82N x 108W then
> doing a sight reduction
> > to obtain azimuth (Zn).
>
> > Ended up deciding there were two problems
> with this; both biggies.
>
> > First, it ignores the earths own magnetic
> anomolies. No help for this.
>
> > Second, it gives me an initial great circle
> bearing when I suspect
> > what I'm really after is a rhumbline bearing.
>
> Great circle is what you want, much the same as
> a fix on a radio beacon.
>
> --
> Mike Wescott
> Wescott_Mike@XXX.XXX
>
Dave Weilacher
.US Coast Guard licensed captain
. #889968
.ASA certified sailing and celestial
. navigation instructor #990800
.IBM AS400 RPG contract programmer
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