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Subject: Re: Electronic vs non-electronic
From: Craig (craig@XXX.XXX)
Date: Sun Oct 03 1999 - 23:22:35 EDT
Was your earlier posting in which I read of the airstip being 2 kilometres
away from the GPS position also 2 km off by celestial determination? The
article and several others were referring to GPS induced accidents. I
believe then the problem is too much reliance on GPS being "high tech" and
infallible, as you indicated. The problem would also occur therefore with
celestial. The map is wrong, perhaps due to earlier celestial mathematical
errors.
Just as a matter of interest, I've been watching the times relayed as part
of emails and my curiosity has been stirred. I would like to request any
who would be willing to participate to include UTC at sending and time zone.
Craig
Columbia, South Carolina 2322 EDT (EDT=UTC-0400)
-----Original Message-----
From: Navigation Mailing List
[mailto:NAVIGATION-L@XXX.XXX]On Behalf Of Trayfors, William
Sent: Sunday, October 03, 1999 23:08
To: NAVIGATION-L@XXX.XXX
Subject: Re: Electronic vs non-electronic
Craig:
I don't think anyone's slamming GPS in favor of celestial. Rather, some
of us are just trying to urge the prudent navigator to use GPS cautiously
(just as you would celestial), rather than take as gospel the digital output
of the little black box. You'd be surprised how many folks seem willingly
to risk their boats and their lives on GPS output alone.
Bill
At 10:58 PM 10/3/99 -0400, you wrote:
>Then I gather the problem is TOO much reliance on GPS because of it's
>perceived "high tech" status. Celestial would presumably not help an
>incorrect chart and therefore GPS is being slammed in favor of celestial
>because GPS is "new-fangled". Am I correct in this assumption? I
realize
>GPS can fail, as can celestial (clouds, delirium, alcohol...). Perhaps
GPS
>is more reliable for most navigators.
>
>Craig
>
>-----Original Message-----
>From: Navigation Mailing List
[mailto:NAVIGATION-L@XXX.XXX]
>On Behalf Of Richard B. Emerson
>Sent: Sunday, October 03, 1999 20:52
>To: NAVIGATION-L@XXX.XXX
>Subject: Re: Electronic vs non-electronic
>
>Craig writes:
> > OK, So which one is the problem? The GPS or the charts? If you are
> > actually at a location and the GPS does not match the chart, would
>celestial
> > match the chart or is the chart wrong?
> >
>
>The chart is wrong. This problem happens, for example, in the South
>Pacific where some survey data is pretty old. BTW, speaking of old
>survey data, even highly travelled areas like the Chesapeake use
>hydrography from the early to mid-40's!
>
>Rick
>S/V One With The Wind, Baba 35
__________________________________
Bill Trayfors <btrayfors@XXX.XXX>
The Washington Decision Support Group, Inc.
Specialists in Advanced Information & Communications Technologies
2401 South Lynn Street, Arlington, VA 22202
Office (703) 838-8784 Tech Support (703) 573-WDSG FAX (703) 838-0019
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