Actually, going bouy to bouy in fog increases risk of collision 'cause that's what most others do. I like to stay off the bouys as far as possible, even if it means not seeing them, which isn't necessary with a chartplotter. I don't believe I ever recommended doing that.
--
Moe
GPS,Depth,fishfinder
Paperless
Frank C -
A Navy sub did indeed collide with an uncharted sea mount not too long ago. Subs primarily use inertial navigation (gyroscopes), supplemented by coming up to periscope depth now and then for a GPS fix or to shoot stars. As to the sonar question, they use a depth sounder since it is localized (you have to be almost right above/below the emitter to hear the signal), but otherwise they stay in passive, or "listening", mode almost all the time. The idea is to be invisible, and if you are actively "pinging" with sonar, anyone listening for a very large radius will know you are there.
- AndyS
A Navy sub did indeed collide with an uncharted sea mount not too long ago. Subs primarily use inertial navigation (gyroscopes), supplemented by coming up to periscope depth now and then for a GPS fix or to shoot stars. As to the sonar question, they use a depth sounder since it is localized (you have to be almost right above/below the emitter to hear the signal), but otherwise they stay in passive, or "listening", mode almost all the time. The idea is to be invisible, and if you are actively "pinging" with sonar, anyone listening for a very large radius will know you are there.
- AndyS
Chartplotter
As to the chartplotter debate:
I've been doing all this stuff for around 20 years, used everything from Omega to Loran to GPS, know how to plot radar and visual fixes at very rapid intervals, etc. I've also used a few very modern ECDIS systems.
I have to agree in part with Mike (aya16): for use on a coastal cruiser or daysailor, for the most part, you don't "need" a chartplotter. I certainly don't "need" it for sailing the Narragansett Bay, or even 20ish miles out to Block Island. But, I have a Garmin 188C. I also have the "real" navigational charts in the water-proof case. I do believe that WAAS or differential GPS is good enough to get you into a narrow harbor entrance in the dark and fog, though. Having used the 188C with the Garmin charts all last season, I am very happy with it and very confident in its' abilities.
I think the best way to describe my use of the 188C is as a "situational awareness" tool. I figure out where I am going on the paper chart, then use the chartplotter to monitor the situation and progress. It has tons of great information: tide tables, perfect atomic timing, course made good versus heading, etc. Heck, the anchor swing/drag alarm feature is almost worth having the thing all by itself - it allows me to sleep a lot more comfortably when alone!
Incidentally, the Navy has recently published an updated instruction which will allow Navy ships to "go paperless" once they have a certain minimum hardware/software configuration and the crew is properly certified. So, even the extremely conservative are learning to believe in the new technologies.
Finally, regarding the function which allows the government to decrease the accuracy of GPS: it is called "Selective Availability" and was turned off on 02 May 2000. Since then, dependence on GPS has become so ubiquitous that if selective availability was turned back on without warning, a lot of bad things would happen. So, I think we'd have fair warning if GPS was going to become intentially less accurate.
- AndyS
I've been doing all this stuff for around 20 years, used everything from Omega to Loran to GPS, know how to plot radar and visual fixes at very rapid intervals, etc. I've also used a few very modern ECDIS systems.
I have to agree in part with Mike (aya16): for use on a coastal cruiser or daysailor, for the most part, you don't "need" a chartplotter. I certainly don't "need" it for sailing the Narragansett Bay, or even 20ish miles out to Block Island. But, I have a Garmin 188C. I also have the "real" navigational charts in the water-proof case. I do believe that WAAS or differential GPS is good enough to get you into a narrow harbor entrance in the dark and fog, though. Having used the 188C with the Garmin charts all last season, I am very happy with it and very confident in its' abilities.
I think the best way to describe my use of the 188C is as a "situational awareness" tool. I figure out where I am going on the paper chart, then use the chartplotter to monitor the situation and progress. It has tons of great information: tide tables, perfect atomic timing, course made good versus heading, etc. Heck, the anchor swing/drag alarm feature is almost worth having the thing all by itself - it allows me to sleep a lot more comfortably when alone!
Incidentally, the Navy has recently published an updated instruction which will allow Navy ships to "go paperless" once they have a certain minimum hardware/software configuration and the crew is properly certified. So, even the extremely conservative are learning to believe in the new technologies.
Finally, regarding the function which allows the government to decrease the accuracy of GPS: it is called "Selective Availability" and was turned off on 02 May 2000. Since then, dependence on GPS has become so ubiquitous that if selective availability was turned back on without warning, a lot of bad things would happen. So, I think we'd have fair warning if GPS was going to become intentially less accurate.
- AndyS
-
aya16
- Admiral
- Posts: 1362
- Joined: Fri Feb 18, 2005 6:29 am
- Location: LONG BEACH CALIF Mac M 04 WHITE
Well lets get this straight. If you dont have a Garmin your dead meat. And if you dont use a chart plotter your boat is awfully inadequate for any type of coastal cruising.
If you insist on taking the boat out in harsh conditions and you have a Garmin chart plotter your going to be all right for the most part.
Now real world experience: In low visibility situations, the last thing your brain will tell you is the GPS is right on. Just the opposite your brain says you cant trust it, even if its spot on. Been there and any body that can tell me they have a different experience, you have bigger ones then me. Add the sound of breakers hitting rocks, fog horns, large diesel motors and life gets down right scary.
In fog the water is calm most of the time. If youre not in a shipping lane or near the rocks or if for the most part safe. Kick back, stay there. Wait for the fog to clear. At least where I live that only takes a couple hours.
Now while you sit there ask your self why youre there in the first place?
Why didnt you listen to your garmin radio and get a weather report before you went out? Do you really want to go charging around with a half dozen other boats looking for the marina? Garmin Chart plotter or not.
I think that when some people take their boats out they will see that its a fun boat, It needs little and if the weather is fine and on long runs (4-5 hours) you can actually see a mile or so away to that entrance to the marina.
Now I never meant to give the impression that chat plotters are not useful, but if you use some common sense and avoid fog bad weather or
Hangovers you will have a great time with or with out a Garmin. Now im here in Calif. and I can tell you it would be a bad idea to go sailing right now in ohio, you got a storm coming tomorro and some wind. So I wouldnt go out today.
hull I can see Catalina from Marina Del Rey where I boat most of the time. And its 35 miles away, I can even see two harbors, where I would most likely be going in Catalina.
Come on guys Im just trying to inject some common sense here. These little boats can take a lot but your not going to have a pleasant time in the conditions some talk about. And the Garmin is not the only game in town.
I feel like a surfer trying to catch a few waves and some guy sitting on his board on the beach that never surfed trying to tell me what the best board is to use and how to use it.
Some here need to get some stick time.
Your Chart plotter will not tell you about the telephone pole partly submerged in your path. I actually hit one sailing and it was sunny.
I plan on a chart plotter soon. Just because Iam toy oriented. I will use it to go to Catalina just like I did a hundred times before without GPS or chart plotter. I think it will add to my enjoyment.
Now how many people have sat in their cockpit staring at a paper map, for hours on end while under way? Not me. And when we go to far off places on the trailer Ill have plenty of time to get a clue as to where Im going and where we want to sail to. With the chart plotter that will be easier. So it does have some usefulness. But if where Im going is fogged in Ill stay on the trailer and wait for better conditions. I have enough finger nail scares on my arm from just leaning 25 dgr.
Anyway I guess some have figured it out and ill admit it Im a hard head and freely say so. But I have a soft spot in my head that will allow good common sense information to leak in and change my mind. And I try not to impose thoughts of mine without some consideration for the differance in the use of those thoughts. In other words each situation could be totaly differant for everyone. There is noooooooo pat answer to much of anything.
Moe and I are having a tiff here, and I would like to extend a hand to agree to disagree. hull Moe Ill fly us up to the alien ship and you can up load the virus, ok? Loved that movie.
But I still think the Lowrance with the nauiticpath software would be a better choice for us trailer sailors.
If you insist on taking the boat out in harsh conditions and you have a Garmin chart plotter your going to be all right for the most part.
Now real world experience: In low visibility situations, the last thing your brain will tell you is the GPS is right on. Just the opposite your brain says you cant trust it, even if its spot on. Been there and any body that can tell me they have a different experience, you have bigger ones then me. Add the sound of breakers hitting rocks, fog horns, large diesel motors and life gets down right scary.
In fog the water is calm most of the time. If youre not in a shipping lane or near the rocks or if for the most part safe. Kick back, stay there. Wait for the fog to clear. At least where I live that only takes a couple hours.
Now while you sit there ask your self why youre there in the first place?
Why didnt you listen to your garmin radio and get a weather report before you went out? Do you really want to go charging around with a half dozen other boats looking for the marina? Garmin Chart plotter or not.
I think that when some people take their boats out they will see that its a fun boat, It needs little and if the weather is fine and on long runs (4-5 hours) you can actually see a mile or so away to that entrance to the marina.
Now I never meant to give the impression that chat plotters are not useful, but if you use some common sense and avoid fog bad weather or
Hangovers you will have a great time with or with out a Garmin. Now im here in Calif. and I can tell you it would be a bad idea to go sailing right now in ohio, you got a storm coming tomorro and some wind. So I wouldnt go out today.
hull I can see Catalina from Marina Del Rey where I boat most of the time. And its 35 miles away, I can even see two harbors, where I would most likely be going in Catalina.
Come on guys Im just trying to inject some common sense here. These little boats can take a lot but your not going to have a pleasant time in the conditions some talk about. And the Garmin is not the only game in town.
I feel like a surfer trying to catch a few waves and some guy sitting on his board on the beach that never surfed trying to tell me what the best board is to use and how to use it.
Some here need to get some stick time.
Your Chart plotter will not tell you about the telephone pole partly submerged in your path. I actually hit one sailing and it was sunny.
I plan on a chart plotter soon. Just because Iam toy oriented. I will use it to go to Catalina just like I did a hundred times before without GPS or chart plotter. I think it will add to my enjoyment.
Now how many people have sat in their cockpit staring at a paper map, for hours on end while under way? Not me. And when we go to far off places on the trailer Ill have plenty of time to get a clue as to where Im going and where we want to sail to. With the chart plotter that will be easier. So it does have some usefulness. But if where Im going is fogged in Ill stay on the trailer and wait for better conditions. I have enough finger nail scares on my arm from just leaning 25 dgr.
Anyway I guess some have figured it out and ill admit it Im a hard head and freely say so. But I have a soft spot in my head that will allow good common sense information to leak in and change my mind. And I try not to impose thoughts of mine without some consideration for the differance in the use of those thoughts. In other words each situation could be totaly differant for everyone. There is noooooooo pat answer to much of anything.
Moe and I are having a tiff here, and I would like to extend a hand to agree to disagree. hull Moe Ill fly us up to the alien ship and you can up load the virus, ok? Loved that movie.
But I still think the Lowrance with the nauiticpath software would be a better choice for us trailer sailors.