To Plot, or Not ? Is a Chart Plotter a Luxury or a Necessity ?

[skenn_ie]

Use GPS, but don't depend on it. Keep an hourly mark on a paper chart, and be able to navigate using paper/pencil/protractor. Quite apart from equipment failure, you never know when the military are going to switch it off, or put an offset in.

[noelex 77]

Originally Posted by skenn_ie

Use GPS, but don't depend on it. Keep an hourly mark on a paper chart, and be able to navigate using paper/pencil/protractor. Quite apart from equipment failure, you never know when the military are going to switch it off, or put an offset in.

If you are worried about the gps system failing ( and I think the risk is extremely remote) then remembering a distance and bearing to a know waypoint is usueful. The two numbers can be easily remembered, unlike latitude and longitude. The numbers are constantly updated so you are not relying on an old fix if the gps goes down. The biggest advantage is there is no need ( unless you want to check the paper chart) to constantly mark or write down your position.

[virginia boy]

Originally Posted by noelex 77

If you are worried about the gps system failing ( and I think the risk is extremely remote)

Remote but not improbable, nor without precedent.

FAA warns of ongoing GPS issues in southeastern US due to Defense Department 'tests'

https://www.faasafety.gov/files/noti...L11-01_Rel.pdf

[wolfenzee]

aside from the conspiracy side (which is actually quite real) there are other factors that might cause GPS error. Even then you still have to think of the possibility of electrical malfunction...probably the most likely cause of GPS error.

[LJH]

Originally Posted by wolfenzee

Even then you still have to think of the possibility of electrical malfunction...probably the most likely cause of GPS error.

I have to agree. Three days into a 1500 mile passage I had "LOST GPS FIX" and lost my position on both chart plotters. Turned out to be wire fatigue on a wire soldered to the GPS antenna circuit board. You should always have a back-up paper map available if needed. Don't forget that between GPS errors and cartography errors your position on the chart plotter could be more than 1/2 mile off.

[noelex 77]

The two chartplotters should be fed from different gps units.
Even with one chartplotter two fixed gps units ( at least one with a seperate display) are a good idea. A simple switch will change which gps unit is feeding the chartplotter.
Finally you need a handheld gps with a good supply of batteries.
The gps is such an important instrument it deserves backups.

[carstenb]

Let's get real here. I'm old enough to remember when automatic transmissions for cars were not highly thought of because they might fail and lock the wheels up etc etc etc. Virtually all technological advances have a bunch of old f*rts saying what will you do if it fails?

I sail with both a chart plotter and paper charts. I know how to navigate by DR and I know how to use a sextant (and I do use it). Having said all that, a GPS or a chart plotter makes life a lot simpler. NO reason not to have one - no reason not to use one.

Byt the way - anybody remember all the negative comments that were made when furling genoas first came out? How many boast do you see without them today?

[s/v Beth]

One thing (which was hinted at earlier) that the chartplotter absolutly excells at is the ability of the crew coming on to quickly diagnose nav errors and correct them before it is too late. When I get "Cap, can you come up here for a minute?" I can see their prior course, their current course and with a quick glance around where they are and which way the boat is positioned. The boat is almost always pointed in the right direction (although not always) but the current is usually taking the boat away from the target. My chartplotter is set up to show that instantly as well.
Useful tool I think.

[Stumble]

The idea of going offshore without a chart plotter just doesn't work anymore. While huge touchscreens are a luxury, a simply 7" is pretty much required in my book.

I would add at least one if not more completely independent backups (iPhone, iPad, or handhelds). Plus paper charts for the area you are going to be in.

[Sabbatical II]

My new boat which is nearly ready to launch is having CP, radar & AIS, paper charts & a certificate in the draw that says I can navigate without all that. Having had chart plotters lose signal in the middle of dark nights amongst islands in the Barrier Reef, I continue the dicipline that I was taught to plot our actual position on the chart every hour. So the chart becomes the thing I rely on, everything else is just nice to have. I had to make the same decision on whether I would fit a bowthruster (42' 12.5t boat). I chose not to and so have had to learn how to manoevre in close quarters and spring off etc. I see bowthrusters used in benign conditions many times that only required a careful conservative approach. It seems to me that if we use these gadgets when simple good seamanship will suffice, we lose the ability to manage without them when the little button doesn't work. While it's nice to have the "nice to haves" there is a definite dumbing down of the required skill level to skipper a boat load of people who believed us when we said we knew what we're doing.

[noelex 77]

I think part of the problem is that some people are very uncomfortable using technology and others are uncomfortable using the paper alternatives.
I have always thought CP were very easy to use, but recently I had a very experienced salor and boat builder on board. He was a great navigator, but was totally lost learning to use a chartplotter. It would have taken weeks to get him competent using this technology.
I would encourage crusing sailors to become comfortable using all the tools.

[charliehows]

i use a hand held gps - i finally gave up using my sextant when i realised the gps was the most accurate clock on the boat, but all i use it for is position which i then plot on a paper chart - mainly because i love paper charts, dont care how much they cost. As for chart plotters - if you enjoy using them go for it i say. i prefer pilot charts for harbours etc., and i dont think ive ever had a paper chart disappear off the chart table at a critical moment...

[reefpilot]

is it possible to use S63 vector charts on opencpn? They are encrypted S57's

[Littlechay]

Originally Posted by Stumble

The idea of going offshore without a chart plotter just doesn't work anymore. While huge touchscreens are a luxury, a simply 7" is pretty much required in my book.

I would add at least one if not more completely independent backups (iPhone, iPad, or handhelds). Plus paper charts for the area you are going to be in.

I disagree, you do not need a chart plotter offshore at all. Offshore a chart plotter is useless, especially a small one. Zoomed out it will show how slowly you are crossing your bit of ocean, zoomed it it will show you a little boat icon on a blank screen. They are power hungry and will scoff your batteries whilst giving you very little useful information.

Inshore is where a chart plotter is useful, IF, you are sailing in an area with accurate charts. You can and should always check pilotage on a paper chart because that can be used for traditional position fixing even if there are significant distortions, beware of just plotting a GPS position onto the charts as that is what the chart plotter is doing, same difference.

I'm fitting out a boat now and not including a chart plotter, I'll have a instruments, a furuno RD33 display and a Vesper watchmate AIS transponder as my main situational awareness tools offshore - radar too for night and poor visibility. All this provides all you need and more, offshore.

Inshore I have a laptop chartplotter running Maxsea TZ as a preference because it works so well with OpenCPN for this areas where I have my own special charts. Inshore I'm more likely to be using the engine to give the batteries a boost so power isn't such an issue. Offshore I use the laptop daily to check email and get a GRIB file in.

A word of warning on the iPad and iPhone. As they are 'assisted GPS' devices their GPS will often not acquire a position offshore. If you want a backup it has to be a proper stand alone GPS.

IMO
Chris

[noelex 77]

IPad have 2 different models the 3G model has no gps and uses the phone towers to get a position, so will not work offshore. The wi fi model has a proper gps chip so it works offshore.
One advantage of the iPad is that the maps are cheap. In many parts of the world the maps do not agree, so multiple map sources are invaluable.