T&T: NOAA charts

[Candy Chapman and Gary Bell]

A few days ago Ed K reported:

I bought a DVD off e-bay that has all the raster charts plus a copy of
Seaclear II. Yes you can download all of that for free off the internet. But
it does take a bit of time and effort to download all the charts. The bonus
was a PDF instruction manual for seaclear. The writer of the seaclear
program provides no instructions and no support so the pdf manual is of some
value. Paid about $10. Now I have all that on a disc. I can load seaclear
onto the laptop & let it play the charts off the DVD. No connections to the
e-bay seller.

Ed K


I haven't noticed a reply that pointed out how perishable navigation 
charts are.  I have a couple more days of summaries to catch up on, so 
if I am being doubly extra redundant again some more, please forgive and 
forget. 

In the Navy, mumblemany years ago, we always had a Quartermaster aboard 
who's entire off-watch job it was to comb through each week's printed 
Notice to Mariners and carefully edit the changes onto every chart we 
could ever possibly use, including a bunch of classified ones.  Daily he 
risked electrocution from his electric power eraser and inadvertent 
tattooing from his drawing pens. He was easily recognized by his ink 
stained fingers.   We were home ported in Long Beach, so we didn't 
correct the Great Lakes, Atlantic coast, European or the Atlantic coasts 
of Africa and South America, although we did have a goodly number of 
those aboard.   All normal charts bear a note about the latest 
corrections applied when they were printed, and we carefully noted each 
of our corrections as well.   We corrected publications like the Light 
Lists too. 

Anyway,  coastal erosion and sand bar deposition happen continuously; 
rivers change their courses and build ever larger or smaller deltas; 
sand bars appear, move about and disappear; rivers, harbors and atolls 
silt up and are dredged; volcanic islands pop up; rocks and reefs are 
still being discovered (paints a picture doesn't it!); navaids come, 
change and go at an alarming rate;  jetties, moles and breakwaters are 
built and destroyed; etc. etc..   This move to downloadable 
electronically filed charts is an huge improvement which allows 
everybody to keep up with all the corrections, in a fashion much easier 
than the old paper trail.   Cheaper all around too, for the users and 
particularly for the guv'mint.  Saves trees too.  Sadly, because of the 
constantly growing flood of changes to our charts, even the electronic 
charts are about as perishable as produce. 

Of course nobody in their right mind uses all that detail when they are 
merrily swanning about their home cruising grounds on a lovely afternoon 
-- but bring up a nice fog, get delayed into unfamiliar darkness, have 
to divert to an unfamiliar place, or even simply fail to hear about a 
new sand bar or a freshly discovered rock, and those details can become 
verrrry important.  Try finding a charted buoy that's been moved or a 
channel that's silted up since you last came that way.... 

I check out the latest correction date of any CD chart sets I find, and 
I will delay my purchase until just before setting out on a significant 
trip.  I then have an encyclopedic set of electronic charts, which are 
reasonably current.  Then, just before using them I download updated 
charts for the route I plan to actually use.  I have regular paper 
charts and/or chartpacks for passages outside my regular home cruising 
grounds, and before a trip I scan the corrected electronic charts for 
things I need to note for my route on the paper chart. Often I print out 
detailed harbor or obstruction charts from the electronic database.  
Perhaps it is because of my background, or my obsessive nature, but 
whenever I am away from my immediate home cruising grounds I watch my 
electronic charts as I drive (I use radar overlay to distinguish traffic 
from navaids etc.), and I also plot our track on an appropriate paper 
chart.  After the trip I leave the plot on the chart, and have it as a 
reference for my next trip over the same ground.  I still proceed with 
some caution -- I have personally found stuff that got into Notice to 
Mariners, and you could discover an uncharted rock or missing navaid 
too.   

Obsolete chart information is never a bargain.  We take risks whenever 
we go boating, but it makes poor sense to intentionally set out with 
inferior information. 

Regards,
Smudgy