Why Man (sic) cannot navigate by GPS alone...

A forum for discussing topics relating to MacGregor Powersailor Sailboats
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Catigale
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Post by Catigale »

Lets bookmark this link - next time Im lost on a desert island I can ping the IP, download the details, and know exactly where i am....

That is a great kids science project though....along the same vein, there was an astronomical determination of the speed of light made within 0.2% accuracy in the 17th century by the Danish Astronomer Roemer.

WHen someone told me about this I spent a week trying to figure out how he did it, to no avail....and that was with me knowing the right answer already so I could use the benefit of trig and bodies in motion to put a strategy together.

All of this proves how wicked smart some of these folks were back then before they had all these worldly concerns like VPNs and why my Excel cells arent formatted correctly...
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Night Sailor
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Post by Night Sailor »

There's no question that one needs an alternative to electronic or electrical navigation aids once beyond the sight of land. Knowledge and the skill to apply it is simply prudent. Piloting and dead reckoning require the constant involvement of the crew, but it's as successful now as it has been for thousands of years before electronics and satellites.

Only a relative few can always sail in deep water. I would venture a guess that about 75% of all inland and coastal cruisers in the US, in all types of boats, spend most of thier time sailing in water less than 10 fathoms. It's simply the lay of the land where most of the sailors live. Especially true on the East, Florida and Gulf coasts. That is definitely shallow water with all the hazards you can think of, and definitely the reason we bought our Macs instead of the rtraditional deep fin keel boats. Popup centerboards and rudders have an enormous advantage in convenience and safety.

Navigation and local knowledge go hand in hand in shallow water. Charts, even the latest are not to be taken as accurate because in many places they literally change with every storm that goes through, named or not .
eric3a

Post by eric3a »

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Last edited by eric3a on Tue Mar 11, 2008 7:53 am, edited 1 time in total.
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deacm
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Post by deacm »

Gee, I wonder what brand GPS that cruise ship in Santorini was using last week............Ronco? :-)
eric3a

Post by eric3a »

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Last edited by eric3a on Tue Mar 11, 2008 7:54 am, edited 1 time in total.
zuma hans 1
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Post by zuma hans 1 »

'Bout three years ago a yacht sailed directly into one of the oil rigs off Huntington Beach. It was simple GPS math:

Sleeping skipper x (Autopilot using Oilrig as waypoint) = (toppled mast + boat stuck under oil rig) x salvage job.
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