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16-01-2020, 09:44
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#16
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Registered User
Join Date: Jul 2005
Location: Bellingham
Boat: Outbound 44
Posts: 9,319
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Re: Traditional or digital navigation - which is safer?
We Pilot exclusively digitally. End up with a lot less plotting errors that way.
__________________
Paul
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16-01-2020, 09:54
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#17
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Registered User
Join Date: Oct 2019
Posts: 771
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Re: Traditional or digital navigation - which is safer?
When we crossed the Atlantic lightening took out the masthead amplifier of our Satnav some 300 miles south of the Canaries. Fortunately we had bought a cheap plastic sextant in Gib and the tables. Our sights were accurate to about 30 miles and that was good enough for us to find Barbados.. After that we invested in a good sextant, but we never were required to use it, but I would not cross and ocean without it.
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16-01-2020, 09:59
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#18
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Registered User
Join Date: Apr 2018
Location: Scotland
Boat: 42ft Moody Ketch
Posts: 643
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Re: Traditional or digital navigation - which is safer?
Always, as said in some good comments , digital does not give the big picture or detail of topography of a paper map, but digital is easier to keep at the helm and watch it.
Always plan with the paper and plot and know my course and waypoints, then keep tablet at helm with OPENCPN and glance at it periodically. A simple 60 dollar GPS will do the same Job as any thousands of dollar equipment,
To truly understand navigation and how tides and currents and winds can have an effect on the boat and to understand navigation fully a good chart based knowledge is essential for good seamanship , tis why it is taugh in the Navy and Merchant Navy.
But the caveat is always a chainsaw in the hands of a numpty is still a dangerous item
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16-01-2020, 10:02
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#19
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Registered User
Join Date: Jan 2020
Posts: 1
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Re: Traditional or digital navigation - which is safer?
When I started I used the RDFs and a chart. My father would like to double check with his sextant. The fun was both of us going over the charts together. GPS is super accurate but I miss the bonding over the table looking at charts and deciding where we are or where we are going. I take out the charts and show my granddaughter where we are going because they might not even have paper charts when she is older. They don't teach cursive writing anymore which will make it a specialty to be able to read anything I wrote by hand. Though my wife says she can't read it now anyway.
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16-01-2020, 10:33
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#20
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Registered User
Join Date: Nov 2014
Location: Atlanta, GA
Boat: Catalina 30
Posts: 704
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Re: Traditional or digital navigation - which is safer?
Quote:
Originally Posted by RichMac
Do some sailors still navigate with safety using just paper chart plotting and a sextant?
Or have we all switched off our navigation brains, and been seduced by the convenience of GPS?
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GPS gives you a very accurate fix on your location on the surface of the globe, as well as a manual sighting done correctly does. The danger is people assume since GPS is so accurate the chart is also accurate. Digital charts are usually made from paper charts, and some areas the paper charts are based on data gathered with rope logs and lead soundings (if not outright dead-reckoning) from hundreds of years ago.
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16-01-2020, 10:40
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#21
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Registered User
Join Date: Sep 2015
Location: East Coast Florida
Boat: Chris Craft 38 Commander 1965
Posts: 482
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Re: Traditional or digital navigation - which is safer?
I am a firm believer in digital navigation - with the understanding about confirming it mentally with my knowledge of dead reckoning and how that works. Started going to the Bahamas before there was Digital navigation using paper charts and RDF radio sigtnals, compass. Then got LORAN when it came out -no graphics only line numbers which had to be cross referenced with a paper chart -then came early rudimentary graphics which was still worthless except when used in combo with a paper chart. Then Loran in combo with PC navigation software - a huge step forward in my estimation (raster charts only). Problem was that Loran did not reach all portions of the Bahamas so paper charts and Guidebooks were still very much needed.
Along came GPS and yearly incremental upgrades to the digital charts library and more and more information.
My current setup has Garmin Chartplotters and an PC with OpenCPN with my paper charts nicely rolled up in their tube and a Chart Kit Spiral bound set of charts- also tucked away for safe keeping.
There is no way I would want to go back to paper only. As far as inaccuracy that some talk about with the digital charts - that has not been my experiences.
Literally hundreds of times I have been going along in new waters and see a shoal or even a lone rock marked on the chart and looked over and there it was - hundreds of times.
Paper charts are great and the charts I normally have displayed on the PC are usually RASTER copies of paper charts so I can see the traditional reference material - but digital tells me Exactly where I am on the chart - within feet. Not a mile or so by any math or paper chart calcs with a sextant.
Digital charts combined with electronic instruments (PC or Chartplotters) also tell you a myriad of other bits of info. Course, heading, distance to next waypoint, total distance to go, time to go, time of arrival, tide info, speed, depth, an on and on.
I think if you asked an old sailor from the days of Nelson if they thought that today's digital navigation would be an advantage in war for them they would have jumped on it in a heart beat.
I went thorough the series of Power Squadron charting and navigation courses and electives and they provided a great foundation and understanding and interpretation of data and all these years of experience with electronic forms of have made me feel safer.
Last point - would airline pilots and bombers rather use paper charts and compass or digital navigation? No contest.
Using paper is fun as a mental exercise but not too helpful in my daily boating.
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16-01-2020, 11:02
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#22
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Registered User
Join Date: Mar 2012
Location: Madeira Park, BC
Boat: Custom steel, 41' LOD
Posts: 1,402
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Re: Traditional or digital navigation - which is safer?
As seems to be fairly common for me on here I'm going to buck the expressed conventional wisdom and say digital beats paper hands down. Perhaps a big part of that is that I used paper for so many years and I'm perfectly comfortable with them - but it's SO nice to see that little boat icon move across the screen/chart nestled on its shelf in the binnacle (Scorpius is tiller steered so there's no wheel in the way) when you are navigating a place like Murray's Labyrinth with dozens of underwater rocks just waiting for you and an undulating, nearly featureless surrounding landscape. A paper chart on the nav table down below or spread on the bridge deck just doesn't cut it.
Offshore I note our waypoints on paper so if all of our computers, or all four battery systems or all of our many charging systems fail, I can still navigate with one of the handheld gps's.
One point I'm not sure has been mentioned in this thread is that chart accuracy, particularly with digital, is critical. With paper, when piloting or "conning" in tight spots, you HAVE to look around to know where you are. The chart tends to be for reference to indicate specific spots to avoid - given that you know where you are and can quickly find it on the chart. However, with digital it's possible to get mesmerized by the display screen and just steer to the plotted route - or even worse, have the autopilot hooked into the chart plotter such that the boat follows the course line automatically. DANGEROUS! Our charts are pretty good but a couple of times I've been merrily going down the middle of a narrow channel of the Inside Passage and looked down at the chart plotter to see that we were 100 yards (or meters - it doesn't matter which) inland! If the chart plotter was driving the autopilot, we'd be up on the opposite very rocky shore!
My experience in Central America and elsewhere tells me that charts are generally MUCH less accurate than in North America and Europe. So putting heavy reliance on charts, whether paper OR digital, can be an invitation to disaster when close inshore and I suspect is a major reason people are still running aground despite all the modern electronics aboard.
The BC coast here (my home cruising ground) requires well over 100 paper charts. At $25 a pop (last time I checked) I have neither space nor the necessary funds for them. If you worry about equipment failure, have backups. I have six gps's on board of varying degrees of sophistication. Three are laptops or tablets with either built-in gps's or usb gps dongles. One is dedicated to navigation. The others are generally otherwise used but can step in at the helm if and when needed.
And yes I carry a sextant and current tables and can do celestial (at least noon sights) if absolutely necessary.
Have fun out there!
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16-01-2020, 11:04
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#23
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Moderator Emeritus
Join Date: Nov 2008
Location: Lived aboard & cruised for 45 years,- now on a chair in my walk-in closet.
Boat: Morgan OI 413 1973 - Aythya
Posts: 8,492
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Re: Traditional or digital navigation - which is safer?
I cruised for enough years to be able to recall making mistakes the "chart Plotter" that was the big ruled protractor laid on the paper chart and the digital "chart plotter" that is GPS interfaced. There's always room for human error; therefore, two systems are best for making a mistake apparent. These systems for back-up can be old and new or two plots that are both "new".
__________________
Take care and joy, Aythya crew
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16-01-2020, 11:08
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#24
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Registered User
Join Date: Jan 2013
Posts: 28
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Re: Traditional or digital navigation - which is safer?
Like others, I began sailing well before the advent of electronic navigation. I still carry paper charts, pencils, parallel rules, and dividers.
Most days I rely on the electronic navigational devices. When trip planning I always start on paper and then convert to digital. I really enjoy plotting on charts. By the time I am finished I have things recorded on paper, digitally, and mentally.
My life experience has taught me that everything connected to a battery will ultimately fail.
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16-01-2020, 11:20
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#25
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Registered User
Join Date: Nov 2018
Location: Panama
Boat: Norseman 447
Posts: 1,628
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Re: Traditional or digital navigation - which is safer?
I disagree. A GPS tells you nothing at all about where you are on any hypothetical chart. To niggle details, if the GPS system, satellites and your receiver are all working properly (which will probably be true most of the time), you will derive a position relative to an arbitrary description of the earth (WGS 84) that is most of the time within an error of a a few tens of feet. If that exercise just happens to be wrong, how will you know your calculated position is wrong? Even if it is correct, your position as shown on a chart is dependent on how accurately the chart displays information, which an unfortunate amount of the time, isn’t very good.
A simple example of hidden failure has to do with the use of True vs Magnetic bearings. Your GPS computes them as True. You’re steering compass reads out in Magnetic. Most systems will tell you that they use "magic" and can convert one to the other. But the "magic" is usually a computer model of variation vs position that’s provided by the government. It’s usually good for 5 years, but this year was updated sooner because it was wrong.
So, have you updated you plotter software to get the current model? Do you know what year's model the MFD is using? If you have multiple devices, are they all using the same model? What happens if the model is outdated? Continue using it? Just stop converting?
All electronic nav systems have these kind of issues. To assume that they’re right without being able to check them is just placing blind hope in a system which everyone knows is someday going to be wrong.
Blind faith isn’t a good navigational tool.
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16-01-2020, 12:10
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#26
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Marine Service Provider
Join Date: Feb 2012
Location: Vienna, Austria
Boat: Vagabond 47
Posts: 935
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Re: Traditional or digital navigation - which is safer?
Wrong Question - Not one without the other - for saftety reasons.
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16-01-2020, 13:05
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#27
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Registered User
Join Date: Oct 2012
Location: Guilford, CT
Boat: Bristol 35.5 1978
Posts: 762
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Re: Traditional or digital navigation - which is safer?
Richmac - I use both. helm mounted chartplotter for local day trips..if sailing for days/offshore plan trip on paper and carry same onboard. Install waypoints on chartplotter. Have Richardson 12x18 inch spiralbound charts of varying scales (1:6,024 to 1:50,000) for long island sound and beyond. For Newport to Bermuda use plotting sheet w/ scale of 1:1,058,400 and bermuda chip for garmin. For redundancy, have 2 mounted chartplotters (1 helm, 1 nav station), 1 hand held gps, but no sextant....hope to add the latter this year and begin learning celestial..
I learned to fly (single engine land) 49 yrs ago when only paper, directional finders, and your eyes (visual flight rules) were available...would say, current gps is the gold-standard, albeit moving at 100 knots not 6..
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16-01-2020, 13:12
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#28
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Registered User
Join Date: Feb 2013
Location: Kingston Ont Canada
Boat: Looking for my next boat!
Posts: 3,101
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Re: Traditional or digital navigation - which is safer?
I fear for those who only know and use digital navigation. One day their device won't boot, and what will they do?
A chart plotter is a wonderful device. And I use one. But I always have a paper chart and conventional nav tools aboard and ready, just in case. I also keep a pair of Garmin Etrex handheld GPS as well. These are pretty robust devices which got me across the Atlantic, and all around Lake Ontario.
I still find paper charts far superior when planning and laying out courses.
I can't imagine any trip on Lake Ontario without the Lake Ontario General chart.
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16-01-2020, 14:01
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#29
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Registered User
Join Date: Jul 2005
Location: Bellingham
Boat: Outbound 44
Posts: 9,319
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Re: Traditional or digital navigation - which is safer?
I don't understand all the fear of digital navigation. I unquestionably navigate safer now with digital charts that have my position continually updated vs when I used to navigate with chart, course compass, hand bearing compass running below to update my DR position every hour or so.
And then there were those island approaches where you pointed windward of where you wanted to be, worked in as close as you dare and tried to recognize something on the shore - hoping you got a real fix before running into something.
__________________
Paul
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16-01-2020, 14:36
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#30
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Moderator Emeritus
Join Date: Feb 2012
Location: Carrabelle, Florida
Boat: Fiberglas shattering 44' steel trawler
Posts: 6,082
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Re: Traditional or digital navigation - which is safer?
"A chart plotter is a wonderful device. And I use one. But I always have a paper chart and conventional nav tools aboard and ready, just in case."
Hamburking is right. Chart plotter, sure, and spare GPSs. One in the spare we use for position and speed, one in the AIS, a couple more here somewhere. But, a paper chart with lat/lon updated at 30 minute intervals. Take it right off the GPS. Then when you are hit by lightning, and lose everything electric, you know just about where you are and can do it the old way home.
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Never let anything mechanical know that you are in a hurry.
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