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Robes 12-12-2012 12:53 AM

Gps navigation advise
 
Hello All-

I've got allot of experience for 1 year sailing and currently a member of OPO (Off Shore Passage Opportunities). I have the US Sailing Series "Passage Making" and "Coastal Navigation" which I will start reading soon. I'm wondering if either of these books truly address GPS Nav? ... I'm thinking not?

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MY BACKGROUND:
Within 3 years I plan to buy a boat (refit for blue water) and do some single handed sailing up the east coat of USA, Canada, Iceland, Baffin Bay. When the wife retires (5 years from now) we plan to circumnavigate. I've taken an extensive intro sailing class through the NIH Sailing Club(National Institute of Health) as well as : ASA 101,103,104.

None of the training thus far has dealt with GPS nav, I can do the chart plotting. I plan to do the remainder of my training by personal education, and hands on experience through OPO. I have daily access to Flying Scots for my weekly fix.
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... I want to buy a handheld GPS. At this point I'm thinking the Garmin 78 series. I will be doing blue water passages hopefully across most of the oceans in the next few years. I want to be an informed buyer yet reading about the units don't really seem to answer the questions, the write ups are very similar between the models.

I'm looking for advise on what GPS to buy (yet, I look at GPS as only a back up to the charts). What available info is there to learn about using it?

I guess each GPS model/make comes with specific instructions as to how to use it?? Will the one I buy come with comprehensive instructions on its use?

Someone told me West Marine may offer lectures/seminars on GPS usage but I can't find any reference to this on there web site, any comment here?

Thanks, Robes

MarkofSeaLife 12-12-2012 08:31 AM

Re: Gps navigation advise
 
Well you have hit on the salient point... That the liars hold court at the moment.

You navigation will be by GPS so you are right to learn it now. You are right there's no books about it. Basically because GPS takes the crap out of navigation and it doesn't need a book, just the instruction leaflet.

Make sure your GPS can plug into a laptop so you can use better/cheaper charts than Garmin. Download CM93 off the Internet, or from a cruising friend, and download OpenCpn a free chart plotter for PC. Then plug the GPS into the Opencpn and you are off and away on a learning experience that will be the basis for all navigation.

I don't have paper charts on this boat and would never sail with anyone that uses them. They are unsafe and obsolete.


Mark

chucklesR 12-12-2012 08:47 AM

Re: Gps navigation advise
 
Mark (above) makes a good point - you will be doing your navigation by GPS.
Paper charts are invariably out of date - I use them for planing, the make great table top discussion / conversation pieces, not so much for actual underway plotting.

As to which hand held chartplotter to get, truthfully it just doesn't matter as long as it is at least a 12 channel WAAS receiver and has updated charts. The basic level charts most hand helds come with are more dangerous than paper chart.

For me, that means get a hand held that can use Navionic's, and make sure you DO in fact register and get updates to the charts.

That hand held will quickly become a back up when you are cruising, it might even become your third or fourth option.
I sail with a Raymarine e7d chartplotter, a Magellan hand held, my android phone with a navionics app, and my note book running PolarView and PolarCOM with full NOAA charts and a hockey puck GP.
The hand held seldom gets turned on - mostly to check speed on my dinghy. It gets stored in tin foil wrap in a zippy ( a mini faraday cage).

Note for the haters - I'm not saying charting via paper is useless, I can and do. I qualified for celestial navigation while working in the Navy on a USNS so I could stand watch (didn't have to, wanted to). Being able to plot your position twice a day is great and provides a nice boost of confidence. Carrying 400 pounds of books and charts is not within my interest groups.

gtod25 12-12-2012 08:52 AM

Re: Gps navigation advise
 
Quote:

Originally Posted by MarkofSeaLife (Post 960348)
I don't have paper charts on this boat and would never sail with anyone that uses them. They are unsafe and obsolete.
Mark

I can therefore assume that you won't be sailing with the US Navy, the British RN or other major Navies/Shipping lines anytime soon. Your boat your choice, not my problem.

Robes, The GPSMAP® 78 Handheld GPS is a good unit and the price is right. The reason that the write ups are similar between models is that they all do the same thing, they calculate your position from a series of satellites and display it in various formats. If you can actually plot the Lat/Long from a Gps onto a chart that would put you in the top 5% of boaters.

Gerry

MarkofSeaLife 12-12-2012 09:15 AM

Re: Gps navigation advise
 
Quote:

Originally Posted by gtod25 (Post 960357)
I can therefore assume that you won't be sailing with the US Navy, the British RN or other major Navies/Shipping lines anytime soon.

Gerry

They all use electronics.

AIS has seen to that. It's illegal for them to operate without AIS so it means it is illegal for them to operate without electronic charts.

Lake Superior Sailor 12-12-2012 09:56 AM

Re: Gps navigation advise
 
GPS is a great thing when its working! but charts are equally great when you know how to work them: & they never have dead batteries,Big plus!...

Barquito 12-12-2012 10:15 AM

Re: Gps navigation advise
 
I agree with most of the above. You will be using a plotter for most of your navigation, and the instruction manual is probably all you need to know how to do that. However, there are coastal navigation skills (ASA 105), that you still need to stay safe. ASA 105 does touch on GPS navigation a little.

travlineasy 12-12-2012 10:17 AM

Re: Gps navigation advise
 
Much of the GPS accuracy is dependant upon the latest updates of the charts held within. Some are older than Methusila, dating back to the 1950s, others are older.

A great example of this was discovered when I was traveling down the Intra-Coastal Waterway a few months ago. The GPS Plotter showed I was cruising on dry ground, at least 150 feet outside the waterway, but within a margin area delineated by a dotted line. I called a friend at USGS about this and he provided me with the details. Essentially, the chart was created prior to the construction of the ICW in that area. Consequently, the location revealed by the GPS/Plotter was accurate, but the charts portrayed where the proposed ICW was - not the actual location where it was eventually dredged.

The same is true in the ICW on your charts behind Virginia's Barrier Island. All the markers are in place, but there is NO channel - it was never dredged. So, from Oyster north to Wachapreague, the ICW may be on your charts, the same charts within your GPS, but it does NOT exist in that location. Instead, the ICW in Maryland and Virginia is essentially Chesapeake Bay.

So, the argument of paper charts V/S GPS plotter is pretty much mute - the accuracy of the charts is the same. The big difference is the accuracy of the device is far superior, often with an error factor of +/- 9-feet, depending on the number of satellites tracked at any given time.

For me, the GPS/Plotter is among the most valuable navigational tools any captain can have aboard his or her vessel. THE most valuable tool is your eyes, followed by common sense.

I use the Lowrance HDS7, and it's an incredible machine.

Good Luck,

Gary :cool:

JonEisberg 12-12-2012 10:45 AM

Re: Gps navigation advise
 
Quote:

Originally Posted by chucklesR (Post 960356)
Paper charts are invariably out of date - I use them for planing, the make great table top discussion / conversation pieces, not so much for actual underway plotting.

How are your electronic charts more accurate than the properly-updated government paper equivalent they are based upon?

Or, is Navionics now doing their own surveys of the world's waters, now? Goggle Maps and satellite imaging are now calculating water depths, as well?


Quote:

Originally Posted by travlineasy (Post 960403)

A great example of this was discovered when I was traveling down the Intra-Coastal Waterway a few months ago. The GPS Plotter showed I was cruising on dry ground, at least 150 feet outside the waterway, but within a margin area delineated by a dotted line. I called a friend at USGS about this and he provided me with the details. Essentially, the chart was created prior to the construction of the ICW in that area. Consequently, the location revealed by the GPS/Plotter was accurate, but the charts portrayed where the proposed ICW was - not the actual location where it was eventually dredged.

Gary, if your plotter put you on dry land anywhere along The Ditch, something is very wrong, whatever charts or apps you're using are piss-poor... Such a thing can indeed happen in many places, but in using my the C-Maps my own Simrad and many other units use, and a variety of other e-charts I've used, they've always been pretty much spot-on for the entire length of the ICW... I've been placed in the wrong lane on the NYS Thruway, or on the wrong side of the railroad tracks along the Erie Canal, for instance - but I've never been placed on dry land anywhere along the US East coast, that I can remember...

Something's very wrong with your setup, that simply shouldn't be happening in the location you describe... I find it inconceivable that any modern e-charting software would be using information/surveys that pre-date the actual creation of the ICW...

chucklesR 12-12-2012 10:50 AM

Re: Gps navigation advise
 
Quote:

Originally Posted by JonEisberg (Post 960421)
How are your electronic charts more accurate than the properly-updated government paper equivalent they are based upon?

Simple answer Jon - I update my chips monthly with a simple download that takes 5 minutes. How often do you update paper?

As a radioman in the navy I tracked the thousands of hydrolants (messages to up date charts) and watched the quartermasters (navigators) doing the updates. I have no intention of doing that, and most sailors don't either.


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