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Chart/pub corrections.
From: Jeremy C
Date: 2010 Dec 1, 05:14 EST
From: Jeremy C
Date: 2010 Dec 1, 05:14 EST
Greg wrote:
How do you organize a set of trip charts (paper) for bridge use or is everything done in a seprate chart room? Do you have them in numerical sequence and folded/ unfolded. Do you ink the chart number on the back of the chart by the margin? What is the chart correction process these days?
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I could write a long essay on chart correction procedures these days.
They have changed dramatically in the last few years.
First the easy ones:
For a give voyage, the chart catalog is consulted to get the chart numbers
of various scales which will be needed. Those charts are then pulled out
of storage and placed in the correct order of usage (using a binder clip to keep
them together). They are then usually corrected and the waypoints and
course lines then plotted.
Our bridge has a limited set of drawers that contain the charts that are
routinely corrected which include the local area as well as charts to the places
we are most likely to go. The remainder are stored in a closet.
Since we are on the naval distribution list, we have a nearly complete catalog
of charts. We are missing some of the odd harbor and river charts, but
basically we cover most of the navigatable waters of the world.
As new charts come in, they are indeed folded so the blank side is out and
numbered in the corner along with the edition number so that we can quickly
determine if a new chart is a new edition.
Updating the ECDIS is simple. We are sent CD-ROM's with update
patches. They can then be uploaded to the computer and the charts in that
area are corrected automatically.
I spent most of my time as navigator in 2001 and 2002. At that
time we used the more familiar old system of getting weekly notice to
mariners in paper booklets. You then found the applicable corrections for
both the charts you are using and the navigational publications. You then
kept the booklets filed in case you had to correct an unexpected chart.
You kept the booklets on file until the summary of corrections came out.
That was then, this is now. NtM are no longer published in paper
form. You now get them emailed automatically (or through a service the
screens the entire file for applicable entries and only send you the needed
entries) or download them off of the web. They have also divided the NtM
into corrections for paper products and another website for purely digital
publication corrections. They only publish a few of the publications in
paper now, many of them, such as sailing directions, are only available as pdf's
and are corrected in an entirely different process.
Once you download the NtM you either use the pdf on a screen to make
corrections, or you print out the needed pages and do it that way. I
prefer the latter as I can put the paper on the chart and reference it
easily.
The electronic pubs have something called PDU's. They are essentially
patches that you apply to the pdf file of the publication and it automatically
corrects the publication. If you want a hard copy, you have to manually
print it in whole or part. For voyage planning, we typically print out the
applicable sections we need.
Getting these updates can be expensive over satellite connections, if
possible at all. My company also sends out CD's periodically on which they
burn the NtM. That is delayed many weeks, so we typically download them on
the ship when we are around somewhere with an Internet connection.
Summary of corrections are also available via download and CD-ROM.
That's it in nut shell. Electronic pubs and charts are obviously much
easier to correct, especially the vector based charts. It also saves a lot
of time for the typically over-worked 2nd mate.
Jeremy
In a message dated 11/25/2010 11:53:25 P.M. Central Asia Standard Ti,
gregrudzinski@yahoo.com writes:
Jeremy,
Greg Rudzinski
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