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Old 10-01-2015, 09:32   #151
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Re: Another foundering how do chart plotters get it wrong

Posts in this thread acknowledge charts for a variety of reasons have innacuracies. Those of us who have lived long enough realize from experience - not only our own but others too - that electronics used for navigation can and do fail. In the first case, the logical assumption is if charts contain innacuracies, we should accept detail and features are approximate in their location and plan accordingly. In the second case, we should rely on multiple sources when navigating; the best resources being attached to our head.

Not new. Old hat. Contained in the COLREGS and most books on navigation. Splitting hairs arguing about the relative advantage of one electronic device or method over another is great if your objective is to make or lose points in a forum online. But, doing so doesn't change the fundamentals.
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Old 10-01-2015, 09:36   #152
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Re: Another foundering how do chart plotters get it wrong

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Originally Posted by Group9 View Post
You just remind me of the guy, at seminars, who argues with the teacher and other students constantly, while everyone else, is just wanting to hear what the teacher has to say.
The teacher hasn't said anything. You won't answer any questions posed - just make blanket statements and demand they are accepted without question.

OK, I am accepting it, but asking you to provide your solution:

"Please feel free to suggest a solution. Outlaw them? Require licensing? Require courses and testing?

Really, what do you guys suggest?
"

Please help us teacher.

Mark
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Old 10-01-2015, 09:43   #153
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Re: Another foundering how do chart plotters get it wrong

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Originally Posted by Wrong View Post
Posts in this thread acknowledge charts for a variety of reasons have innacuracies. Those of us who have lived long enough realize from experience - not only our own but others too - that electronics used for navigation can and do fail. In the first case, the logical assumption is if charts contain innacuracies, we should accept detail and features are approximate in their location and plan accordingly. In the second case, we should rely on multiple sources when navigating; the best resources being attached to our head.

Not new. Old hat. Contained in the COLREGS and most books on navigation. Splitting hairs arguing about the relative advantage of one electronic device or method over another is great if your objective is to make or lose points in a forum online. But, doing so doesn't change the fundamentals.
No argument here - I am perfectly acceptable of all types of navigation - sextants, DR, paper charts, electronic charts, electronic devices.

One must also admit that all of those above can and do fail. Particularly the person using them.

I have been arguing against the exclusion or damning of certain types of navigational tools instead of the damning of people using them improperly, or demoting these tools to being only useful for "backup or confirmation" purposes.

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Old 10-01-2015, 10:11   #154
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Re: Another foundering how do chart plotters get it wrong

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No argument here - I am perfectly acceptable of all types of navigation - sextants, DR, paper charts, electronic charts, electronic devices.

One must also admit that all of those above can and do fail. Particularly the person using them.

I have been arguing against the exclusion or damning of certain types of navigational tools instead of the damning of people using them improperly, or demoting these tools to being only useful for "backup or confirmation" purposes.

Mark
Does it really matter which puts a sailor on the rocks - misuse or the tool - when reliance is primarily upon the tool for navigating safely? In either case, a safe passage may have been achieved by using the tools attached to our head, and or other available tools.
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Old 10-01-2015, 12:07   #155
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Re: Another foundering how do chart plotters get it wrong

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Originally Posted by Wrong View Post
Does it really matter which puts a sailor on the rocks - misuse or the tool - when reliance is primarily upon the tool for navigating safely? In either case, a safe passage may have been achieved by using the tools attached to our head, and or other available tools.
I think we are violently agreeing and trying to make the same point.

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Old 10-01-2015, 13:32   #156
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Re: Another foundering how do chart plotters get it wrong

Quote:
Originally Posted by MarkJ View Post
From a friend who knows....Quote:
Hey there Mark. .......
That area is notorious for moving sand and shoaling. There are also numerous approaches to get to where they were heading. Some I would never approach at night. Some I have done during the day and it was hair raising. So as a paid navigator in numerous Hobart races I would stand off the approaches to Flinders Island till daylight unless you had a previous track from a few weeks prior.

The boat concerned had just won every division of their race to Hobart so don't think they were novices. Just too keen to get in for a beer at the pub.
The area around the Pot Boil and Vansitartt Shoals is the bit that is dodgy with the constantly shifting banks... I doubt much has changed offshore from Gull Island ( bottom right) for the last hundred years or more.

Certaintly not novice racers but as said before possibly not the most prudent of navigators.

Sail-World.com : Melbourne to Hobart Westcoaster Race yacht aground on return voyage

Nothing new under the sun...

Final Report: Grounding of M/V OLIVA on Nightingale Island, Tristan da Cunha, 16 March 2011 | Potters Weal
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Old 10-01-2015, 13:59   #157
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Re: Another foundering how do chart plotters get it wrong

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Originally Posted by colemj View Post
Yes, I have had those types of teachers who demanded one simply accept what they say as truth and would not engage in logic and reasoning outside their narrowly accepted and defended belief system.

Mark
If a teacher had to argue with thirty students over four plus four equaling eight, very little learning would happen.

You are there to learn from the teacher. If you think the teacher is wrong, find anther teacher that you agree with.
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Old 10-01-2015, 14:22   #158
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Re: Another foundering how do chart plotters get it wrong

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Originally Posted by El Pinguino View Post
Indeed... I'll bet Will Oxley experienced more than just a touch of deja-vu that night on ALVIMEDICA, standing by in the aftermath of the TEAM VESTAS WIND grounding...

How've you been, Frank? Where do you have your boat now?

Apologies for the formatting below...

Two Australian Sailors Lost During Flinders Islet Race | Sailing World

http://www.byc.com/files/Flinders_Incident_Summary.pdf

Quote:

The Cruising Yacht Club of Australia (CYCA) ran an overnight Category 2 race on
November 17
th
2009. One of the marks of the course was Flinders Islet. The vessel
Pricewaterhouse Coopers (PwC)
hit this islet and was lost. Two members of the crew
died...

...

This incident would have been entirely avoided if
PwC
had successfully rounded
Flinders Islet, as hundreds of other yachts have over the past decade.
The root cause of
this incident was over reliance on electronic gps/plotter navigation
. This
resulted in: (a)
failure to keep a proper watch looking outside the boat (rather t
han just at the plotter
screen)
either visually or by radar
, (b) a planned rounding with only meters to spare and
failure to set a conservative rounding distance given the n
ight time conditions, and (c)
no ‘traditional’ navigation (setting clearing depths or clearing lines) to double check the
plotter...



Navigators must be reminded forcefully that gps plotters do NOT see or show a true picture of the world. The gps signal can degrade and the chart can be inaccurate. The
plotter must be paired with
navigation that does in fact actually see the real world

deck
watch, radar, and depth sounder



The islet position is charted to +
-
50m. The GPS system had a particularly poor satellite
geometry at the time of the incident with a horizontal error about twice it’s typical error
level. The combined charting
and gps error could have been 100 meters, and 300meter
might have been a prudent rounding distance at night


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Old 10-01-2015, 14:33   #159
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Re: Another foundering how do chart plotters get it wrong

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Originally Posted by rwidman View Post

Quote:
Originally Posted by Jon Eisberg
Well, there's the rub...

Call me old-fashioned, but I'd prefer to know where I am in the Real World...
OK you're old fashioned!

If you're out of sight of land or even out of sight of landmarks, you don't really know where you are in the "real world".
It appears you're missed my point...

Your position as indicated by GPS on a chartplotter may not always necessarily accurately reflect your position on the Earth's surface - watery, or otherwise, whether you're in sight of land, or not...

Perhaps Evans Starzinger says it better than I'm able, copied from his summary posted above:

Quote:
Navigators must be reminded forcefully that gps plotters do NOT see or show a true picture of the world. The gps signal can degrade and the chart can be inaccurate. The
plotter must be paired with navigation that does in fact actually see the real world - deck watch, radar, and depth sounder
...
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Old 10-01-2015, 14:57   #160
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Re: Another foundering how do chart plotters get it wrong

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Originally Posted by colemj View Post
Here you go Jon - for next time you visit.

BTW, it doesn't even appear you chose good charts. Here is the CM93 chart for your area.
Well, one thing I'm certainly not very good at, is choosing charts/software that may not yet exist... ;-)

My first visit to Newfoundland pictured above was in 2008, if memory serves. I was using the current C-Map charts, upon which the CM93 chart you pictured is based... As previously mentioned, C-Map was then considered to be the best available coverage for Atlantic Canada by people like John Harries, who is pretty well acquainted with that region...

I've never used a computer for navigation, but even so back then OpenCPN was not available for my Mac... Steve Jobs did not unveil the iPad for another 2 years, I believe, so the plethora of e-charting options we enjoy today was not available back then...

Quote:
Originally Posted by colemj View Post
When I look at the electronic raster charts, I see these details also.

I don't think these failures on your part should constitute damning of electronic charts and charting in general.
I'm not "damning" electronic charting, but rather simply pointing out it may not always necessarily be infallible... Like most everyone else today, I rely very heavily on ECS for my navigation, I simply like to have paper along for the ride, as well, for a variety of reasons...

Other's mileage may vary, as always... One thing I definitely agree with, however, is that Google Earth is an incredibly valuable resource for cruising in regions where charting might be poor, or the datums off... I'm guessing GE will increasingly be incorporated into our ECS solutions going forward...
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Old 10-01-2015, 15:05   #161
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Re: Another foundering how do chart plotters get it wrong

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If a teacher had to argue with thirty students over four plus four equaling eight, very little learning would happen.

You are there to learn from the teacher. If you think the teacher is wrong, find anther teacher that you agree with.
I think you have taken this analogy too far, unless you really do believe that Group9 and Familyvan are the final answers on navigation and navigation systems and should never be questioned.

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Old 10-01-2015, 15:18   #162
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Re: Another foundering how do chart plotters get it wrong

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It appears you're missed my point...

Your position as indicated by GPS on a chartplotter may not always necessarily accurately reflect your position on the Earth's surface - watery, or otherwise, whether you're in sight of land, or not...

Perhaps Evans Starzinger says it better than I'm able, copied from his summary posted above:
This doesn't make sense - one's position indicated by ANY means may not always necessarily accurately reflect one's position on the Earth's surface.

My only problem with these debates, which keeps me hammering on this point, is the strange assumption being made that the mere presence of a chart plotter turns people into zombies and causes them to get into trouble.

I don't see how that is possible. Even without wearing a protective tinfoil hat.

I do agree that tools can be misused, people can make mistakes, and people can be down-right stupid. But I don't see how chart plotters CAUSE this to happen.

It certainly isn't just newbies jumping in boats and getting in trouble, because professional navigators are doing it also. And both bricked boats for decades before electronics were even invented.

Once again, please suggest a possible solution to the problem you detect. Even if that solution is banning all electronic forms of navigation or requiring training and licensing. Simply damning electronics, while complaining about all the problems they cause and people they allow to get into trouble, doesn't accomplish anything.

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Old 10-01-2015, 15:27   #163
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Re: Another foundering how do chart plotters get it wrong

The solution has already been presented. Not by me, but by a body with vastly more knowledge than either one of us. The IMO and all its signatories agree. Over reliance on a single device is hazardous.
You must determine your position by all means available. Which includes ECS if fitted. But every boat (or most) is equipped with a navigator with 5 senses.
So the solution is, research your destination, collect relevant sailing directions and charts, plot your course before hand monitor your progress through all available means, and if you have ecs fitted, use it to verify what more established and reliable tools have already told you.
If your ECS fails to verify what you suspected, put her in neutral, heave to anchor or do what ever you have to do to figure out what's wrong.
This is basic stuff. I can't believe it needs to be explained to an experienced sailor.

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Old 10-01-2015, 15:28   #164
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pirate Re: Another foundering how do chart plotters get it wrong

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Originally Posted by colemj View Post
But let's say all of what you and boatman and familyvan are worried about is true. Please feel free to suggest a solution. Outlaw them? Require licensing? Require courses and testing?

Really, what do you guys suggest?

Mark
I think 99.9% of folk here think they are a great tool.. and a grand addition to the navigational tool chest.. some will learn to use them in classes.. others like myself will learn on the job so to speak.. for others who are younger they may miss the voice saying "Turn right 100 yds.."..
Do you realise how many folk cannot read a road atlas these days..
and that's when they can read...
Believe it or not.. You are part of the solution.. folk will read this thread and hopefully go away not filled with distrust at the 'Devils Tool'... but aware like all things it can have flaws.
I do have faith in the common sense of the many... but am also aware that Darwin must be satisfied...
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Old 10-01-2015, 15:40   #165
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Re: Another foundering how do chart plotters get it wrong

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Originally Posted by FamilyVan View Post
The solution has already been presented. Not by me, but by a body with vastly more knowledge than either one of us. The IMO and all its signatories agree. Over reliance on a single device is hazardous.
You must determine your position by all means available. Which includes ECS if fitted. But every boat (or most) is equipped with a navigator with 5 senses.
So the solution is, research your destination, collect relevant sailing directions and charts, plot your course before hand monitor your progress through all available means, and if you have ecs fitted, use it to verify what more established and reliable tools have already told you.
If your ECS fails to verify what you suspected, put her in neutral, heave to anchor or do what ever you have to do to figure out what's wrong.
This is basic stuff. I can't believe it needs to be explained to an experienced sailor.

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That is all just basic navigation and has nothing to do with chartplotters specifically. It applies without a chartplotter on board, as well as with one. If you substitute "ECS" with "compass" or "sextant" or "depth sounder" or anything else in your above post, it would mean the same thing.

But you have already blamed chart plotters for causing problems - both in the context of the title incident (with absolutely zero evidence yet) and in general.

They do not cause problems, or force people to do things they otherwise would not. They are a tool that can be used, abused, misused or not used - just like everything else.

That is such basic logic that I can't believe it needs to be explained to a high school graduate.

BTW, not every navigator possesses 5 senses, but this is a trifling, unless you think they should be banned…

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