On 20 Dec 2004 07:58:48 -0800, wrote:

Having read the responses to and comments on my original post, I am
still left with a few questions:

If I am on the Bahama Bank or in the Bahamian Exumas or in Hawk Channel
off Key Largo or in a bay or "river" or "creek" off the Chesapeake Bay,
negotiating shoals on a cloudy and windy day and GPS goes out because
it was suddenly turned off, is that not an "end" for me?


You reference to the Bahamas reminded me of a epsilon in the Sea of
Abaco in 1992. We were in our way back from a visit to Green Turtle
Cay. We were approaching the Whale Key Passage, about to go out into
the Atlantic and then back into the Abacos. Ahead of us were two
sailboats about to do the same. One had a stopped. The other radioed
him and asked if he was coming through. he responded that his GPS
had failed and he did not know where he was. All he had to do was
look around use his chart.


Does anyone believe or expect GPS to be turned off only for a few
minutes or hours? I would expect weeks to months, or longer, of "ended"
signals.

GPS will not be turned off world wide. It may be turned off in areas
of conflict. GMDSS is closely integrated with GPS. Turning off GPS
would endanger lives.


And mo Would anyone want to be in a commercial or private airplane
when making an initial approach in low ceiling weather to landing and
having GPS suddenly go off? This may well be an "end."

Commercial airline pilot rely on radio navigation beacons and flight
controllers to stay in their assigned air space. Instrument landings
also use radio beacons.

I would suggest that EVERYONE take a coastal navigation course. You
still have to understand tides and currents, chart symbols, compass
reading, plotting, the buoyage system, and position finding.

Jack

__________________________________________________
Jack Dale
Swiftsure Sailing Academy
Director/ISPA and CYA Instructor
http://www.swiftsuresailing.com
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