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Old 01-15-2016, 03:28 PM   #17
koliver
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City: Saltspring Island
Country: BC, canada
Vessel Name: Retreat
Vessel Model: C&L 44
Join Date: Nov 2007
Posts: 3,262
" hope they get this all resolved before we head north. I will also be updating my navionic chips...."

By all means update. Just don't count on your up to date Navionics to have caught everything, as the update is only as good as the programmer and the source material she uses.

Extreme example: We chartered in Turkey in 2007. The boat came with a chart plotter, same as here. Also had a paper chart. Singular! The guide book cautioned that the paper chart was based upon a survey done by a guy named Beaufort and could be as much as 1 nm off what your GPS will say. Beaufort is the guy who originated the "Beaufort Scale" in 1805.
The chart plotter was based on the same survey so no better. Luckily, in that part of the Med, hazards are pretty obvious in most conditions, so the chart is less important than say BC, where you can't see much over 5 ft down.
Point is, the charts, plotter chip, CD or placemat chart is no better than the source survey, so looking out the window still needs to be your primary form of navigation.
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