My Charts Make Me Nervous

[SayGudday]

Every time I look at the my chart books to plan a safe passage I get a little nervous. These are the things I rely on to keep myself and my vessel safe. The details are important. So when I see that the text on the cover is spelled Chart Boooks....I kinda wonder what other details have slipped by them.

Merry Christmas.

[eliems]

Yes, I am using (relying on) iSailor Charts and the creators, (Russian) don't speak english very well. It does not exactly instill a sense of confidence. When I get into close quarters I am watching the deapth guage very closely.

Then of course there is the disclaimer every time the software initiates that says I agree not to rely on them!

Still it has not let me down so far.

https://www.youtube.com/watch?v=N-KkBnoNoLc

I use the paper charts as confirmation for tricky areas as well.

[SayGudday]

Well my paper charts are Chapmans! They have no excuse. Still, I once worked for a company called Battery Assist and on all their business cards, etc. they had spelled it battry, so these things happen I guess

[Cotemar]

You guys have to get out more.
Once you run aground a few times you will have what they call Local knowledge.

[jackdale]

Originally Posted by eliems

I use the paper charts as confirmation for tricky areas as well.

One of my favourite anchorages, if I can get a spot at the very end.

The tricky bit is actually behind you in that video. The rock is right at the second rock face along the port side. The is also a tree branch over the water on the strabord side. Favour to the starboard side on entry.

[SayGudday]

@ Cotemar, I once started a journey with a fella who has been sailing since moses was a lad and he ran us aground 15 feet from the slip. And then again at Morro Bay. Other than that it was a great voyage. Concerning way to start though.

[Wavewacker]

Well this puts another spin on charts, I always assumed charts would be correct, like a topographic map. So, we have difierent chart makers, had no idea, (that's how green I am). I also assumed you got charts from government agencies, guess not.

I know there are charts available for the Mississippi and other commercialized rivers, but I never needed one with my power boat (in all my years I only lost one prop, knock on wood).

This is a subject I need to study, I assume you're reading contour lines as to depth and points of hazards with informational points described in the legend. I suppose your location is determined by time, speed and direction as with aviation. Ahhh, the sextant, nice looking contraption for the coffee table but I have no idea how to use one, it's in the same category as a slide rule for me. (I use calculators)

Where would an old grasshopper go to study chart reading without having to buy charts of areas you'd never go to?

I'll be using as GPS, BTW. I also assume I'll be using software, a laptop/notebook hooked up to the GPS and depthfinder.

[Hudson Force]

I used some "Life Calk" to seal the installation of my "Humminbird" depthsounder. 'doing well so far!

[boatman61]

There are areas where charts are very accurate.. then there are others that have things which have not been confirmed in any way since 17 o Plonk....
Around Europe the charts are pretty damn good and I still use charts that are over 10yrs old... the only changes being that most of the bouys have disappeared.
But in general I tend to get around the world ok... just do not believe everything I read and keep a wary eye on the depth sounder for close in work....
In the Pacific I found anchorages were often up to 3-5 times deeper than stated on the chart... and a few banks and reefs that were a fair bit shallower than my CM93/opencpn said....
There's a good reason for that warning at start-up... aint stress a wonderful thing...??

[hpeer]

Nuff said.

Use your eyes, ears, sounder, and radar.

That black squiggly line in the center is my track. South coast of Newfoundland.

Pea soup fog, all fjords look alike on radar. I found the bell buoy, then ran an offset, now trusting that I had the right fjord on the radar.

Not my only example.

[sailorboy1]

Originally Posted by SayGudday

....I kinda wonder what other details have slipped by them.

well the only thing to do then if you are worried is to get another set of charts, but don't start thinking the new ones are more accurate

the only time a chart is likely to be truly accurate is the day the data is collected, assuming it is using modern instruments

when was the last time you saw a survey team in your local waters?

[SayGudday]

Originally Posted by Don Lucas

well the only thing to do then if you are worried is to get another set of charts, but don't start thinking the new ones are more accurate

the only time a chart is likely to be truly accurate is the day the data is collected, assuming it is using modern instruments

when was the last time you saw a survey team in your local waters?

Reminds me of a funny story. I have friends cruising mexico so i thought i'd do something nice and get them accurate charts (we all know the mexican charts have a reputation for not being too accurate). SO, full of the confidence of ignorance, I say to my mexican wife's relatives "Hey, you are both marine biologists in mexico, right?" 'yep.' they said. "Can you get me some accurate charts?" asked I. They laughed for 5 minutes and then asked me if I could get them some more accurate charts.

[carstenb]

Any of you that think charts, paper or otherwise, are accurate......

Many charts are based on soundings taken over 100 years ago. these soundings were taken the old fashioned way, with a man throwing the lead. The lead was thrown in rows, 100 meters apart. sea bottom in between was extrapolated. In many areas, nothing has been done since.

Some countries are recharting using side-scanning sonar etc. This is very accurate, but generally this activity is not a high priority and when it is done, the major shipping channels are done first.

I believe that in the pacific, there are still areas where the charts are based on data collected by Captain Cook.

Even here in Denmark, a thoroughly western country with a long tradition og sailing (also big vessels), many of the charts are suing data collected during the 1800s

And it ain't no different in your country.

[SayGudday]

OK, I'm going to have to fess up now and say I started this thread as kind of a joke because I figured a bunch of you would all jump in and say "Yeah I noticed that on my chart boook too!"

[sailorboy1]

Originally Posted by SayGudday

OK, I'm going to have to fess up now and say I started this thread as kind of a joke because I figured a bunch of you would all jump in and say "Yeah I noticed that on my chart boook too!"

We'll try to keep this in mind for your next thread now that you admitted to being a troll.