Thank Gd for GPS

[Lagoon4us]

Originally Posted by myosys

In 2001, the Ambrose Light tower in lower New York Bay was crushed by a 500' freighter that put the nav point right on the light tower! How's that for piloting, eh?

Anyway, another tool one can use in unfamiliar waters are recent satellite photos. Especially useful in shoal areas (NJ ICW) . In google earth, one can go back a few years and depending on the time of day, you can see the low tide shoaling, etc and mark your course accordingly.

Back in 1981 we used aerial photographs of The Great Barrier Reef by finding matching underwater reefs that aligned with the image of the photo. At the time the charts were not updated since being plotted by James Cook Flinders etc etc

A bit like sophisticated 'crows nest navigation' i guess....

[sabray]

we should add thanks for the depth sound, hand held compass, and flux gate. While talking with god don't forget to mention me though flawed I always try to be helpful or at least entertaining kinda like loran or rdf.

[lookoutnw]

I remember when I was young how they said LORAN / OMEGA was the greatest thing to ever hit the navigation market and that nothing could be better. Now it is said to be GPS. Wonder what is next? But the compass and lead line still seem to be the best 'standby' / 'Old Faithful' of mariners....

[sailorboy1]

Interesting how many here are trashing GPS suggesting everyone using it must be stupid etc and that they don't know how to do basic navigation (just reading your GPS and chart-plotter requires some basic knowledge). When their issue really is just with stupid people.

Using GPS as an example when in fact you are just talking about stupid people in general is a waste of time. Stupid people are just stupid, period!

[Ziggy]

Originally Posted by lookoutnw

I remember when I was young how they said LORAN / OMEGA was the greatest thing to ever hit the navigation market and that nothing could be better. Now it is said to be GPS. Wonder what is next? But the compass and lead line still seem to be the best 'standby' / 'Old Faithful' of mariners....

Sheesh... Can't believe people would trust their lives to these newfangled magnetic compass doohickeys, which a nearby lightning strike can easily demagnetize and make useless! If you can't navigate solely by observing swell patterns, stars, and birds, you shouldn't be on the water.

And don't tell me you actually rely on these chart thingies, drawn by some bureaucrat in a hydrographic office somewhere!

Hrumph!

[bobconnie]

My daddy always said there was only one cure for stupid, and it would seem that still applys to a lot of our current "skippers" out there.To bad it is sometimes a deadly cure !! Come on guys theres some "Captin" courses out there you can even get em on line LOL Learn a little something before you go out to Cruise, it may save your life and maybe mine to !! Just a thought Bob and Connie

[Paul Elliott]

I'm going to name my next boat
False Sense of Security.

Just to make you guys happy...

[shorebird]

When I fist stated using a small hand-held GPS, I decided to use it only to obtain lat and long, and manually plot positions on paper charts, then continue using the compass for bearings ect. It seemed like a good way to "combine" the old with the new, while still making me use the old chart and compass. When I first tested the unit, I kept plotting a position 15 miles away. It was consistent, and the instructions could shed no light on the problem. I finally discovered the readings were given in three options: degrees in decimals, degrees and minutes in decimals, or just degrees, minutes and seconds. Reading in one, while plotting in another would cause an error from small to large depending on the numbers and the error introduced. Since the marine charts I was using used degrees on the chart, and minutes divided into tenths, I used the readout of degrees with decimalized minutes so I could plot them directly on the chart, and my accuracy improved dramatically.
After a couple short cruises, we obtained a chartplotter, and love it, but still keep the charts and compass working and handy.

[S/V Alchemy]

Your tale illustrates that you had enough prior knowledge of how to work a chart and how to do basic navigation to understand that a) you had a problem, b) you could determine a solution, and c) neither chart nor GPS were "wrong", but nonetheless, the interpretation of the data led to errors that could have put you on the rocks or worse.

We have a situation these days in which plotters exist as the sole navigational means aboard, and skippers with sometimes insufficient knowledge to realize they have a problem or, if they somehow do, insufficient learning to discern a solution.

The smashup at Ambrose Light and the Air France plane smacking into the South Atlantic are just two examples of people trying to argue with screens showing a representation of reality instead of looking out a freakin' window to see reality itself.

So maybe this thread should be "thank god for seamanship...it makes using a GPS far more useful!"

[delmarrey]

Originally Posted by S/V Alchemy

So maybe this thread should be "thank god for seamanship...it makes using a GPS far more useful!"

The impression I get from the OP it seems he may have been on the other end of the spectrum. And w/o the GPS may have floundered. Lets hope he buys one and learns its use for himself, now that he has a boat. Even though that goes against my first post #9 on this thread.

[markpierce]

Originally Posted by Mike OReilly

Yah! And how about those new fangled things called engines! We should stop selling fuel to those so-called "sailors" who spend more time running on wind by perkins.

Yes. And here I thought Richmond Yacht Club members were sailors.

[Rakuflames]

Originally Posted by S/V Alchemy

I usually seek out the 10 metre depth contour (or some other arbitrary feature discernable by depthfinder...or even a leadline) and because I keep a DR and an hourly log on passage (yes, even in the sunshine), I can usually suss out where I am even in fog. And if I can't, I look for five metres and drop anchor until it clears up.

If you've kept compass bearings and have maintained "situational awareness" (like noticing the time when you pulled abeam of some properly charted nav aid), you can usually puzzle out your location by working backwards to "last good fix". Lastly, if you are in trouble, you can get the CG to try to get an RDF fix on your transmissions, which will yield bearing to safety. Using your ears helps, too. If you are sailing slowly over 10 metres of depth, and you hear surf or obviously nearby shoreside sounds (taking into account the ability of sound to project out over the water), you look for the part of the chart with the steep drop-off. If logically, and proceeding from your last good fix, you could be at that spot, you probably are. That's a new "not so good" fix in that it's going to be a bit wobbly, but it's a smaller circle than "this miles-deep fogbank".

Another use of sound is if you are running parallel to cliffs, use an air horn and count the time until you hear the echo. That will give a rough offing and can be done at 3 AM. You'll know a) there's that cliffy bit and b) you are X nm away from it.

There are many places here where you can be 30 miles from shore and not have 10 metres of depth.

[Rakuflames]

Originally Posted by mjwarner

I think one of the biggest issues I hear about is that while GPS has made navigation easier and safer for us who know how to use it as a tool to be used in conjunction with charts and DR fixes, there are a lot of newer boaters out there who don't know enough about the basics of navigation to compensate for the fact that a GPS unit or chart-plotter does NOT get you from point A to point B automatically. Case in point are putting in a waypoint, but forgeting about set and drift and wondering why they went aground on a shoal they had skirted (supposedly) when they had first plotted it out on the GPS. Or setting a waypoint and not factoring in the sandbar, or island between them and their waypoint. ( "the marina was on the OTHER side of the island.)They think they can set it up, engage the autopilot and sit back and enjoy the ride. There is a lot more to basic navigation than just deciding to "go over there" that a lot of these folks on the water have no idea about, and I find that rather scary.

They'd have to not know how to use the chartplotter, because even a little 441 gives you all of that.

[Rakuflames]

Originally Posted by Don Lucas

Interesting how many here are trashing GPS suggesting everyone using it must be stupid etc and that they don't know how to do basic navigation (just reading your GPS and chart-plotter requires some basic knowledge). When their issue really is just with stupid people.

Using GPS as an example when in fact you are just talking about stupid people in general is a waste of time. Stupid people are just stupid, period!

I agree with you. People can have the most expensive equipment money can buy and still do stupid things.

[Rakuflames]

Originally Posted by Ziggy

Sheesh... Can't believe people would trust their lives to these newfangled magnetic compass doohickeys, which a nearby lightning strike can easily demagnetize and make useless! If you can't navigate solely by observing swell patterns, stars, and birds, you shouldn't be on the water.

And don't tell me you actually rely on these chart thingies, drawn by some bureaucrat in a hydrographic office somewhere!

Hrumph!

"Sheesh... Can't believe people would trust their lives to these newfangled magnetic compass doohickeys, which a nearby lightning strike can easily demagnetize and make useless! If you can't navigate solely by observing swell patterns, stars, and birds, you shouldn't be on the water."

Uh huh.