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hriehl1 11-13-2010 06:30 AM

GPS / ChartPlotters; Totally Baffled
I am moving up from years of inland lake daysailing to a Hinterhoeller HR28 we'll sail in Casco Bay Maine. So for the first time in my life I need to be concerned with navigation beyond simple line-of-sight. I have spent probably 4 hours at Garmin and Lowrance websites, and primer-level information just does not exist... they tell you WHAT features a given unit has but not WHY you want/need that feature.

So... a few questions.

1. What would be the drawbacks to a minimalist electronic approach? Like simply a hand-held GPS? When visibility is good, I intend to rely on paper charts and triangulated position fixing if I need to know EXACTLY where I am. But in essence, navigating the "old fashioned" way appeals to me more than sitting there looking at a color screen. The hand-held GPS, capable of providing an exact real-time fix, would be relied on more for fog / low visibility situations.

2. Garmin handhelds and entry-level chartplotters come with US Coastal "BaseMaps" but then it seems they want more $$ for BlueChart maps. Their site is very poor describing what one does and does not get with Basemaps and BlueChart upgrades. Basic question... do Basemaps provide enough info for safe coastal sailing in low visibility conditions, or is the BlueChart upgrade necessary?

3. In addition to GPS (or maybe entry-level Chartplotter) I only plan to install a depth sounder. I've done enough small-boat sailing that I don't need / want speed or wind instruments (I can also get SOG from a GPS). Looking at the traditional sailing providers (Raymarine, et al) , depth sounder / transduver combos go for $400 +/-. A Wal-Mart fishfinder with thru-hull transducer is $125. What am I missing here?

Thanks in advance for your thoughts.

JimsCAL 11-13-2010 08:18 AM

Everyone should have paper charts. Even a large chartplotter can't match the size and detail of a paper chart. Going with a handheld GPS and paper chart is great inexpensive solution. Did it for years. The most useful feature is waypoints. No need to plot positions on the chart from a string of numbers. You know direction and distance to your next mark in realtime. Look for a unit with a builtin database of the USCG marks. No need to enter the data (and possibly make a mistake). With an inexpensive graphing unit, its just a matter of finding the mark on the screen map, selecting it, and your done.

Suggest you reconsider a speed instrument. The log feature in particular is very helpful in DR navigation.

bljones 11-13-2010 08:41 AM

hriehl, a couple of years ago I was in the same position you are in- I have money to spend and no idea how to spend it.
To answer your questions:
1. handhelds are fine in a small boat, and fine as a redundancy on a big boat. BUT, the screen is smaller than even the smallest fixed mount, so unless you have eagle eyes or the ability to keep it close to hand in a cluttered cockpit, it's not my first choice. Also, because it is handheld, by definition it is going to be easier to lose overboard than a fixed mount.

2. Basemap quality varies from manufacturer to manufacturer- for example, the Lowrance/Eagle unit I have has very good base cartography... for the US. Since I live in Canada, there is no base cartography included, so I had to buy a Navionics card. BUT, that $200 Navionics card also enhanced the US basemap, with more info on marinas, additional depth info, etc. If you are crusing in US waters only, you can get by with just the base map on the Lowrance units- I don't have any experience with garmin.

3. You can buy Chartplotter/depth combos, which is more economical than buying two stand alone units, and you can usually display the depth info three ways, either as a text overlay over the chart screen, or in split screen mode, which will give you two displays on one screen, charts and bottom profile, or as a full screen display, and you can "toggle" between chart display and bottom display.

I still do most of my routing by hand on good old fashioned analog charts first, and throughout a sail I like to practice my dead reckoning skills, BUT, i have found that the chartplotter has improved my sailing skills, because i can get almost realtime feedback and verification of the changes i make in sail trim, crew placement, and it is good for providing "at-a-glance' verification of position, distance travelled, distance to destination, etc.

With the right plug and play inputs, you can slave your autohelm to your plotter. I haven't bothered, but it can be a nice feature for some.

SEMIJim 11-13-2010 08:59 AM

We're in a shallow lake, full of hazards, and connected rivers, creeks and canals with wildly varying depths. We have 5' of draft. So, yeah, we depend greatly upon GPS/chartplotter + depth sounder. (I've got the sonar for the GPS/chartplotter, but have yet to install it. We're using the plain old depth sounder that came with the boat.)

Charts are wonderful. Charts are great. Charts are essential. So is the ability to navigate by dead reckoning and piloting. I know how to do these things. And, in fact, I have to do them on the little stink-boat, cuz she's got no electronics.

But I wouldn't be w/o our GPS and depth sounder on Abracadabra.

Btw: You don't steer your boat by staring at the GPS/chartplotter and other electronic aids, like playing a video game. You check them occasionally to verify. Same with wind instruments.

Well... except for the depth sounder when things get marginal... or the other instruments when racing... Or in heavy fog (I imagine). But most of the time you're just sailing, and scanning the instruments as you do the dashboard of your car.


Gene T 11-13-2010 09:01 AM

I sailed for years without because they were unavailable (years ago) or too expensive. Then I got a Garmin hand held that I used for years on several boats. Worked great. The new boat has a Raymarine Color Radar/chart plotter that is almost impossible to use but has lots of features. Yes it displays more info but I seem to spend more time fiddling with it than should be needed.

The newer units are simpler to use, the older Raymarine I now have requires going to the manual frequently just for simple stuff. The learning curve is high. Garmin has a much better user interface.

A hand held and some paper charts is more than anybody needs. More than that is just stuff to play with, not that it isn't useful at times. A hand held will show you where you are, and you can put in waypoints for harbor entrances which is very handy in the fog. It will not get you past a point however because the maps are not that accurate. Neither is depth.

I also used a $100 fishfinder on the last boat with the puck glued to the inside of the hull. That worked great and actually shows you more about the bottom that a regular depth sounder.


brak 11-13-2010 09:06 AM

1. Hanhelds - this was answered. It really depends on what you want to do. I don't think existing handhelds have screens sufficient for decent chart work. They are fine as a way to get a lat/lon fix and place it on a paper chart.

2. Garmin is getting tricky in their descriptions. I see most of their units come in 3 configurations:
- no chart
- US coastal chart (or sometimes US inland chart)
- Worldwide "satellite enhanced basemap"
Worldwide basemap is exactly as it sounds - a nice picture with little low level detail.
US coastal chart is pretty much a complete chart showing a full amount of Garmin depth, coastline and navaid information. They differ from Garmin's more expensive charts (sold separately) in that they do not include various bells & whistles like photos, additional information etc). They are fully suitable for navigation.

3. You can buy a very good quality Raymarine ST-40 depth sounder + display for $200 at Defender (and probably even cheaper if you look around). The difference between systems is, as usual, quality. My boat came with Uniden "walmart quality" depth sounder installed by PO. It certainly shows what depth it is - but the display is tiny and film that covers it (internally!) hardened and cracked. A knotmeter (ST-40 series) next to it looks pretty good and is more readable.

imagine2frolic 11-13-2010 09:48 AM

I have seen, and read people using iphones. The charts are extremely inexpensive. I think I was $10 for Mexico, and Central America. While in Panama one owner showed me how his worked, and it was really fantastic.

I use a laptop, Maptec charts, and Maptec program. All od the USA charts are free, so that's a huge bonus. We also have a hockey puck type GPS that plugs into the laptop. A used laptop, hockey puck, and free charts. For about $350 you are good to go.

We also have several handhelds, and a wall mounted GPS, and paper charts for anywhere we go........i2f

jrd22 11-13-2010 10:44 AM

I've not sailed (or even been there) in Maine, but I've heard it described as being similar to the PNW where we are with many islands and straits and channels, and poor visibility at times. When the weather is clear and you are in a fairly large body of water paper charts and a handheld are more than adequate, no question. When things get dicey is when a chartplotter pays for itself many times over. I can't tell you how many times I've approached, or been in the middle of, an unfamiliar area in less than ideal conditions and have gotten turned around in my directions from just looking at the paper charts (and in some cases I've also had the radar on as well). Fog is a whole other can of worms. Can it be done with just paper charts, of course, and with the addition of a handheld GPS there is no question you will get where you are going (and back), but the addition of a small chartplotter adds considerable peace of mind at times.

As mentioned above, I also have an I phone with a chartplotter app. and it is quite amazing. $5 I think it was and the charts are all free to download. You can enter waypoints, it gives the GPS coordinates of course, SOG, etc. I think I would prefer this option to even a small handheld GPS because it uses the actual NOAA charts rather than proprietary cartography (raster vs. vector). We use it as backup to the Garmin chartplotter and take it in the dink when exploring or fishing (useful as a depth indicator from the soundings and depth contours).

RocketScience 11-13-2010 10:45 AM

First off, I must say that you are very fortunate to have Casco Bay as your sailing grounds. It is not unlike our own Puget Sound, with their beautiful islands, channels, and coves, -a almost lifetime of sailing. But in the fog, these types of sailing grounds can be the most treacherous, and this is where a chartplotter shines.

Yes, I too have my paper charts and handhelds. Hell, I'm even half decent at celestial navigation (which I would recommend that everybody learn). But when the pea soup fog rolls in down a narrow channel when beating to windward, your nerves will be on edge. You'll want 'real-time', right now, information. And the last thing you'll wanna be doing is running up and down to your nav station, fixing positions. Trust me, been there, done that, -got the shirt.

EDIT: Looks like JRD (fellow Puget Sounder it appears) beat me to the punch. :)

rikhall 11-13-2010 02:05 PM

I highly reccomend this course or something like it:

USPS Educational Department - Using GPS

Well worth the time and money spent!


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