otnmbrd wrote:
Rosalie B. wrote:

I don't know where you are or what kind of boating you intend to do.
But here are some general thoughts.

I haven't seen the necessity to do much updating of any paper charts
we have. I don't actually purchase the large paper charts very often,
although the PO of our boat had a large number of them for the
Chesapeake.

Paper charts are pretty easy to update - you can just write on them.
Getting the updates are more of a problem because the Notice to
Mariners are not organized (IMHO) in a way to make this easy to do.
Outside of the US, the charts are not updated very much. Some charts
may have been done in 1899, and have not been updated since. Or they
may have big blank areas on them with no depths indicated.

You're bundling two different "updatings" together, here.
Corrections from LNM (or yearly summaries) generally involve more
"immediate" corrections/updates for known changes to lights, buoys,
wrecks, shoals, rocks, etc..

The problem is that there are so MANY different locations to get
updated. If you are actively cruising, it is difficult (or at least
it is for me) to keep up with all of the different areas.

And people just don't do it. I've several times heard people coming
down into Beaufort that tried to come in the old channel which has
shoaled over, but it is still on the charts. And when we went to the
Dry Tortugas, I knew that one of the channels was closed, but didn't
know which one until we got there and saw the new markers.

When enough changes have occurred or newer surveys show major changes
you will get a "new edition" of a chart.

That is true - the chart-kit that we got with our boat for the
Chesapeake was seriously out of date in regard to buoys, and so were
some of the paper charts that the PO had.

I also find that updating the computer charts is easier. You can just
buy a CD and use it to update your computer charts.

The fact that basic data on a chart may date to "1899", does not
necessarily mean that the information on the entire chart has not been
updated from/since that date.

Sometimes it does, and sometimes it doesn't. The charts for Bimini
have the island offset from its actual position by about a mile. Some
of the charts you buy have corrected this, and some have not. You
can't tell which is which unless you plot your position.

Personally, the only time I've ever had a problem following the
corrections from LNM is when I've left a chart uncorrected for long
periods, and yes, charts outside the US are frequently updated/corrected.


Sometimes people copy each other's charts or trade charts. If I have
a lot of charts of the west coast of Mexico, and I go through the
Panama Canal into the Caribbean where I meet someone who is going the
other way, we may trade - I give them my Mexican charts and they give
me their Caribbean charts. I hear about this a lot, and I see people
offering charts, but I don't know how often it happens in real life or
how helpful these charts would be.

Not a practice I'd recommend, since you are relying on the other guy to
have maintained his charts up to date.

I wouldn't want to do it either, but sometimes cruisers can't afford
to buy multiple charts. They do this with cruising guides too - some
people make notes and the notes are passed around. Sometimes the
notes get to be a book.

I also have computer charts for these areas, which I do not print out,
but use with a GPS in the cockpit. They show me where I am, and have
the advantage that even if the buoy's are renumbered, I can still see
where I am. If buoy #36 is next to my boat, but the chart says it is
buoy #24, that's OK - I still know where I am.

Yup...... about to run over a wreck/rock/etc., that the corrections
would have shown, causing the relocation and re-numbering of the buoys.

Like in the Alligator River where they've added buoys around a shoal.
I'm not very sympathetic to the power boat that waked me that goes
charging down the river without noticing the new buoys and goes hard
aground.

But that's not what I'm talking about really. If you are right there
in person and paying attention, you can be sure that you are on the
correct side of the buoy, even if it isn't on the chart (that's why I
don't put waypoints into the autopilot for it to follow).

It is just that if you are in the St. Mary's River (GA) and you are
looking to go down to Fernandina and the chart says that you turn at
buoy 24, and you actually turn at buoy 24 instead of the new place
which is now buoy 34, you will be in trouble. Actually if you were
coming in from the sea, you'd probably still be in the entrance
channel. The problem would be when you come down the ICW from GA.


grandma Rosalie