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Old 09-08-2013, 07:18   #46
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Re: GPS as the Sole Means of Navigation.

Only crazy folk reactionaries would want to go back to the pre GPS days re navigation.

It was not the GPS system which was in error, it was the charts, correct the charts.
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Old 09-08-2013, 07:45   #47
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Re: GPS as the Sole Means of Navigation.

In answer to the "usual error" query:

When using celestial in the old days, I never had any real means of measuring error in my positions. In general and IME, with a height of eye of only around 8 feet, if there is any sea running the horizon is uncertain enough to provide a significant error. However, we managed to navigate to and through the Tuamotus without hitting anything, and arriving at the targeted atoll safely. To me, that is the aim of successful navigation no matter what means are used.

And I do appreciate GPS, where overcast skies are never a problem!

Cheers,

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Old 09-08-2013, 08:05   #48
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Re: GPS as the Sole Means of Navigation.

I recall being real proud of taking a noon sight in 1975 and placing myself just ten miles away from my anchored spot. ...'just on the other side of the island!
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Old 09-08-2013, 08:16   #49
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Re: GPS as the Sole Means of Navigation.

Quote:
Originally Posted by Jim Cate View Post
In answer to the "usual error" query:

When using celestial in the old days, I never had any real means of measuring error in my positions. In general and IME, with a height of eye of only around 8 feet, if there is any sea running the horizon is uncertain enough to provide a significant error. However, we managed to navigate to and through the Tuamotus without hitting anything, and arriving at the targeted atoll safely. To me, that is the aim of successful navigation no matter what means are used.

And I do appreciate GPS, where overcast skies are never a problem!

Cheers,

Jim
Good...I know what's out there in terms of probable error..just as boatman confirmed...wanted to see who would respond with what.

For many who have been on here awhile and actively cruise..and have been cruising for a long time especially pre-GPS/LORAN...I had a good idea how you all would respond.

I agree that nav is more than any one system...as I posted before...navigation is the art of confirming where you know/think you are.
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Old 09-08-2013, 09:04   #50
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Re: GPS as the Sole Means of Navigation.

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Only crazy folk reactionaries would want to go back to the pre GPS days re navigation.

It was not the GPS system which was in error, it was the charts, correct the charts.
No one is advocating for turning off the GPS signals, but rather getting people to realize that yes indeed you really need to learn and practice navigational skills beyond simply turning on your chartplotter and following the arrow.

This type of behavior, not knowing how to enter a clearly marked and illuminated channel, is typical of many "sailors" floating around out there.

https://secure.thelog.com/printer/article.asp?c=217045

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The most recent incident began at about 10 p.m. March 26 when the skipper of a 42-ft. sailboat could not find the entrance to San Diego Harbor. Conditions were clear with a high marine layer.

"He was south of the Zuniga Jetty off the Hotel del Coronado and couldn't find the channel due to lights in the background," said Sea Tow Capt. Greg Dreischmeyer.

"He had been stuck searching for the channel entrance for four or five hours and for some reason couldn't get his chart plotter to function; it kept reading data error every time he tried to load the card for the San Diego area."

The conditions were clear, but the skipper couldn't distinguish the channel lights from the background lights. Finally, at about 1 a.m., the rental boat's skipper called the Coast Guard on VHF radio Channel 16. Since the vessel was in no imminent danger, the Coast Guard contacted the private towing firm Sea Tow to lead the craft into the harbor.
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Old 09-08-2013, 09:08   #51
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Re: GPS as the Sole Means of Navigation.

A competent mariner who is proficient with coastal navigation and manual piloting is not the type of person who is unable to enter one of the largest harbors on the west coast on a clear night.

A lack of navigation technique is a good indicator of general piss-poor seamanship (which really shouldn't be shocking considering that a large part of seamanship is navigation).
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Old 09-08-2013, 10:33   #52
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Re: GPS as the Sole Means of Navigation.

GPS contributes to safety as some of the more experienced have said and I agree. Therefore, it follows that failure of a GPS reduces the safety margin. So a backup or two independent from ships power is a prudent measure. Not many pack a sextant in their ditch bag but everyone should pack a handheld VHF and GPS with replaceable batteries. I hope we can turn away from the GPS "bashing" that I see on more than one forum lest new cruisers fail to appreciate the safety features that GPS affords. We rely on many modern inventions that make cruising safer than Slocum's day and there is nothing wrong with that.

I think the example that Rebel Heart brought up has lessons for anyone. The right things happened for the most part. The captain recognized his predicament, called for help, help came and no lives or property were lost. Therefore, all involved are to be commended. I would hope any of us in that situation would have as happy an outcome. Each of us can learn a different lesson from that example but we should try to avoid making judgements and finger pointing. There is enough of that when things really do turn out bad even if all the facts are unknown. But that's a topic for another thread.
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Old 09-08-2013, 11:50   #53
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Re: GPS as the Sole Means of Navigation.

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Originally Posted by transmitterdan View Post
GPS contributes to safety as some of the more experienced have said and I agree. Therefore, it follows that failure of a GPS reduces the safety margin. So a backup or two independent from ships power is a prudent measure. Not many pack a sextant in their ditch bag but everyone should pack a handheld VHF and GPS with replaceable batteries. I hope we can turn away from the GPS "bashing" that I see on more than one forum lest new cruisers fail to appreciate the safety features that GPS affords. We rely on many modern inventions that make cruising safer than Slocum's day and there is nothing wrong with that.

I think the example that Rebel Heart brought up has lessons for anyone. The right things happened for the most part. The captain recognized his predicament, called for help, help came and no lives or property were lost. Therefore, all involved are to be commended. I would hope any of us in that situation would have as happy an outcome. Each of us can learn a different lesson from that example but we should try to avoid making judgements and finger pointing. There is enough of that when things really do turn out bad even if all the facts are unknown. But that's a topic for another thread.
+1 to all of this!

Incidentally, I do have a handheld GPS and bag of long-life batts in my grab bag, but I have often wondered what is the point. After all, you don't do much navigation drifting around in a liferaft . One might want to know one's position in order to relay it to someone over VHF, but my handheld VHF has its own GPS, plus DSC.

As to the guy trying to pick his way into San Diego harbor at night without a plotter -- I have to agree with Dan here. Good seamanship is knowing your limitations and keeping your vessel out of danger. The mariners of old wouldn't enter an unfamiliar harbor even in daytime without a local pilot, much less at night. Poor seamanship is arrogantly assuming that anyone who can't do it -- just like that -- is an idiot. So, Rebel, if it had been you, you would just charge right in, instantly recognize all the lights, and sail right up the channel under full sail would you? It sounds like the pilots who know just enough enough to be dangerous -- most crashes occur just after graduating from the beginner stage, not during the beginner stage. Sorry, Rebel, that is not specifically directed towards you, but at a certain attitude seen around here from time to time.

Disdain of the skills of people less experienced than you is not the mark of a really mature and really skilled mariner in my opinion. It is one thing to reach the level of skill where you start making fewer really dumb beginner mistakes. But only much later comes the knowledge that there aren't any skills in the world which can help you in an endless list of situations which sometimes occur at sea. So you gradually start to understand that we are not nearly as different from the beginners, as we imagine in that first flush of gaining some initial skills. There but for the grace of God . . .

Picking your way into an unfamiliar harbor without a plotter, at night, with the lights washed out against a light-polluted sky, is inherently dangerous. I would never do it myself except in case of a dire emergency (I try to make it a rule to never enter a new harbor for the first time at night even with a plotter). Kudos to the guy who spent hours trying to figure out the lights, and resisting "get-home-itis" -- for hours! -- as long as he was not absolutely sure he had figured it out, and for calling for help after hours of this failed to produce the necessary level of certainty. That's good seamanship -- knowing your limitations, knowing the limitations of the situation, and keeping your vessel safe.
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Old 09-08-2013, 12:08   #54
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+1 Dockhead. That mobo skipper showed appropriate seamanship.

All of us have seen or experienced the issue of determining lights against a busy light polluted background. Anyone who says its easy , hasn't been there


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Old 09-08-2013, 12:08   #55
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Re: GPS as the Sole Means of Navigation.

We entered Charleston Harbor at night in 1972 as beginers. I remember that we were focused on a heading toward a 4 sec. flashing red. At some time we both looked away and came back to our flashing red, but it was a different 4 sec red around a bend and we ended up briefly aground on a mud flat. We scrambled off and on taking several turns until we decided to drop our anchor and think things out. The number of lights were very disturbing. We could make out three bridges as well as the bright lights of a couple of high school football stadiums on this friday night. When we finally identified where the channel was, we could see vessels passing by with their navigation lights ocassionally obscured by dark spoil islands. We made it out by triangulating the bearings to the known bridge locations to find out where we were. That was over forty years ago and we are far more experienced and, to this date, that was the last time I came into an unfamiliar harbor at night!
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Old 09-08-2013, 12:19   #56
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If you can't enter San Diego harbor on a clear night your "limitations" are such that you should take up golf.

There is a racon beacon at the channel markers which extend for ~3 miles off shore. Not to mention the frigging lighthouse, or constant stream of vessels going in and out.

That bonehead couldn't even figure out where he was. The fact that he didn't have a paper chart only furthers his clear incompetence.

And mariners of old waited for pilots because their ships were big, channels were poorly marked, and there were rules.

No one with a 40' modern vessel with operable propulsion and steerage should be so clueless and unable to enter a clearly marked and flat calm harbor.

And if he can't operate a boat outside of a harbor at night, maybe he should have thought of that before he left the harbor and didn't bother to do an eta.

You guys can defend incompetence like this, flyin hawiian, and the Honduran wonder boy all day long. They have no respect for the sea and treat it as such.
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Old 09-08-2013, 12:22   #57
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Continuing with my experience I have anchored outside harbors on the Chesapeake until daylight even though we had good printed and electronic charts with backup GPS. Sometimes I have to recognize that things aren't going right simply because I'm sleep deprived. Four hours sleep and sunshine can make a huge difference.
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Old 09-08-2013, 12:31   #58
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The boat was a rental. So right there we have some unknown facts. We don't know their sail plan but maybe they did not intend to be out past dark. Maybe something happened that prevented returning when planned. Usually these things are due to a chain of events and not just one mistake.

We need to think about what we want other similarly situated people to do and point out what was done correctly. Without more facts I don't believe there is anything in the report that warrants name calling of the captain who properly called for help.
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Old 09-08-2013, 12:39   #59
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Re: GPS as the Sole Means of Navigation.

Not sure what everyone means...

While I agree in today's world.....with even the most basic handheld gps or radar...entering a major seaport should NOT exceed the typical boater's abilities.

A also agree that just entering with the average eyeball using lights can be a handful with a fair tide and some steerageway.

If I remember correctly from my flight safety days...an average adult's night vision decreases by some like 50% each decade between 30-60 yoa.

I'm lucky, partially because of my training and the rest good eyes...but many people I boat with in their 50's and 60's are really hurting for night vision....It certainly is much harder for them to navigate by eye than people with much superior night vision or night navigation training/experience.
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Old 09-08-2013, 12:48   #60
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Re: GPS as the Sole Means of Navigation.

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If I remember correctly from my flight safety days...an average adult's night vision decreases by some like 50% each decade between 30-60 yoa.

I'm lucky, partially because of my training and the rest good eyes...but many people I boat with in their 50's and 60's are really hurting for night vision....It certainly is much harder for them to navigate by eye than people with much superior night vision or night navigation training/experience.
Sheesh, no wonder that the nights have seemed darker since I turned 75!

But really, since I had but average night vision at 30, if your rule of thumb is correct I would be nearly blind in the dark, and that does not seem to be so. I'll admit that it is kinda hard to quantify, but I would be down to a few percent of original acuity and I find that hard to believe. Haven't noticed such a great difference with the vision of younger folks... who knows?

Interesting, though!

Cheers,

Jim
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