# Celestial Navigation



## Slayer (Jul 28, 2006)

This was touched on in the thread below, but rather than hijack that thread I decided to start a new one.

I know little to nothing about celestial navigation, but it seems very complicated and difficult to learn. If you do ocean crossings is it necessary or important to know? Do you have to be well versed in it to benefit from it, or can it still be usefull with some knowledge of it? 

I did an overnight sail and used stars for my bearings for periods of the sail, mostly for steering when I grew tired of checking the gps. So it was helpful to me for that limited use. Are there any recomended books or videos to start learning with?


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## Hesper (May 4, 2006)

It's not as bad as it seems - at least not with the right instructor. I passed the Power Squadron's Junior Navigator course (basic celestial) and even if I never use it, it was worth it. I've never looked at the sky quite the same way since. And yes, even the basic is a good back-up for an ocean crossing for when your GPS batteries get wet.

I tried the advanced course twice, but the conceptual trigonometry was just too much for me. Maybe I'll try again when I get older and wiser. I don't know about videos, but there are plenty of good books. Just hang around a bookstore (not a website) and you'll see.


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## AdamLein (Nov 6, 2007)

It's not necessary, but the prudent mariner etc.

I think the more important question is, do you want to learn it? If not, you can get away without it. If so, it's a lot of fun. However there are a million threads on this site that give pointers to how to get started; I recommend using google to search.


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## SailingIsis (Jan 10, 2011)

These days I think there is very little case to be made that celestial navigation is necessary or prudent. (I think the prudent mariner should have a backup GPS unit)

That is: assuming that the GPS system (NAVSTAR) does not go down for an extended period of time - and even then there are GLONASS and GALILEO systems as backup.

Electronics on board of course can fail, but at the current price of handheld units, having several back-ups is no longer an issue (be sure to put one in your ditch bag or even in your life raft). These will be battery powered and of course it's possible the whole electrical systems fails, but a baggy of batteries will allow you a fix a couple times a day for months. 

That being said, there is a charm and a certain sense of accomplishment to do it the old fashioned way. It can get quite complicated, but some of the basics like a noon shot are certainly not too hard for anyone to master.


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## Omatako (Sep 14, 2003)

The bottom line is that if you want to have a full understanding about how the whole celestial thing works mathematically then you have a task ahead of you.

However, if you can grasp the fundamentals about taking a sight, filling in a basic form, using a plotting sheet and looking up data in manuals, the physics of getting a fix are not difficult to master.

Forms and plotting sheets have been posted on this board several times and a search should locate them. If not, I can help with some, PM me if you wish.

My advice is take a basic course on celestial which will help you understand the terminology and process but don't try to master all the (as others have rightly called it) conceptual trig and other mathematics that go with it. I would advise against trying to learn from a book.


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## Libellula (Aug 20, 2007)

really a very simple answer
Buy a cheap sextant and learn how to take a noon shot
you will be amazed at how simple it is
by doing this then you will begin to see that there are instances when only you can save your bacon
this will also require that you keep up with where you are and how fast you are travelling (DR)
and two GPSs do not work if there is a failure of the system
when one takes off into the ocean be prepared to take care of yourself


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## Omatako (Sep 14, 2003)

Libellula said:


> and two GPSs do not work if there is a failure of the system


Are there still people who believe that the GPS system is going to go down? A hundred or more satellites would simultaneously have to fall out of the sky for the system to fail.

How long does something have to keep flawlessly working before it is universally trusted?

People die due to aircraft falling out of the sky at a rate of a million to one compared to those dying due to GPS "failure" yet we all still trust commercial airlines but not GPS.

Go figure.

Let's face it, celestial navigation is a recreational pastime.


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## btrayfors (Aug 25, 2006)

GPS system failure is a distant possibility, excepting the potential for localized jamming or the USG deciding to once-again implement "selective availability".

However, the possibility of onboard GPS units failing is much greater. Power failures, battery depletion, unit malfunctions, and EMF due to nearby or direct lightning strikes are much more a possibility.

Celestial is a good backup, and it's very good exercise for the brain. I agree that one needn't "master" the spherical trigonometry involved. The noon sight is very easy to learn. So, too, is the noon sight for longitude, which involves taking equal altitude sights before and after meridian passage. Learn these, and if you're interested and so inclined, continue on from there.

Not sure about the plastic sextants. I like good equipment. Good sextants cost a bit, but they're worth it. Get a good used Plath or Tamaya or Freiburger or Simex or Aires sextant. For heaven's sake, don't waste your money on any of the many "replicas" available on the market....they are strictly for show, not serious use.

Bill


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## Boasun (Feb 10, 2007)

Omatako said:


> Are there still people who believe that the GPS system is going to go down? A hundred or more satellites would simultaneously have to fall out of the sky for the system to fail.


The satellites will not be falling out of the sky, they are 11000 miles above the earth. But a major solar flare, a large dither put back in by the military, or jamming by those are enemies or those who think of it is a practical joke. Certain electronic equipement have jammed ship board GPS's. 
Plus you may have not plugged in the correct chart datum. Or position the GPS antenna in the optimum position on your vessel. Bad antenna connection have caused one cruise ship to run aground. And I've had three GPS's go belly up on me, which is a good reason to have all of your way points listed in your Navigation work book AND use secondary means of Navigation to confirm your position.


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## Omatako (Sep 14, 2003)

Boasun said:


> And I've had three GPS's go belly up on me,


That's uncommon bad luck. The hand-held that I use has been functioning perfectly for several years and the others that I have bought for redundancy are still in their original packaging.

Yes, I hear the possibilities of solar flares and the like but it would be interesting hear, maybe in the form of a poll, how many people have been unable to get GPS position for more than an hour or so due to issues not on their own boats.

I personally have never had such an event anywhere I've been in the world so I'm noticeably skeptical.


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## AdamLein (Nov 6, 2007)

I have had more than one occasion where my Garmin handheld picked up zero satellites when I had a clear view of the horizon. At least once was while sailing in open waters, and the condition lasted a couple of hours that time. I gave up waiting, but it worked again the very next day (no change of batteries or anything).


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## Boasun (Feb 10, 2007)

Please note: I was navigating commercially across the Oceans long before they had GPS. And really don't need a GPS to get me from point A to Point B.


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## Omatako (Sep 14, 2003)

Boasun said:


> Please note: I was navigating commercially across the Oceans long before they had GPS. And really don't need a GPS to get me from point A to Point B.


Me too but now that I have GPS . . . . . it's a little like trying to find a call box when I could have a satellite phone in my hand.


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## AdamLein (Nov 6, 2007)

Omatako said:


> Me too but now that I have GPS . . . . . it's a little like trying to find a call box when I could have a satellite phone in my hand.


... which might be a good idea, so that you aren't all rusty at finding call boxes once The Man or The Sun or Zeus or whoever comes and shuts down your satellite phone. Assuming you're concerned about that.


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## TQA (Apr 4, 2009)

The OP asked for any book recomendations.

Celestial Navigation for Yachtsmen by Mary Blewitt demystifies the process.

I liked it and know of many others who also learned from it.

BTW GET A PLASTIC SEXTANT TO LEARN ON! Lots on fleabay. You might even find one is a marina skip!


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## rikhall (Feb 7, 2008)

Back to the original question:

Ya - if you feel like it - it is not hard to learn. Trig is NOT my strong point, but, you don't need to understand trig to do elestial nav.

My wife and I both took Celestial Nav (and both passed it) with the Canadian Power Squadron group - and it was fun. Taking sites is not all that hard to do and neither is working out the positions. Just takes patience, practice and someone who can teach it to you.

If you are inclined - go for it.

Rik


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## jackdale (Dec 1, 2008)

CN is really a case of use or lose it. I took the course 20 years ago. Trying to get back into it using Tom Cunliffe's book.


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## derfus (Jan 12, 2011)

If it works....there for it will at some point break.


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## svs3 (Jun 23, 2006)

I have often used CN to back up GPS and vice versa. It's a good tool to have in your toolbox. You never know when it might just save your butt.

For me it offers a direct connection to all the mariners that have gone before and that alone makes it worth learning. 

Also, I believe as sailor anything increases your connection to environment is a good thing. When I sail long distances I get into a routine of regularly logging such things as sea state, barometer reading, wind direction and strength, clouds, and a host of other variables that affect sailing. CN dovetails very nicely into this more traditional, less automated, mode of navigation and sailing. Taken as whole, this practice has taught me more about the art of sailing and made me much more appreciative of the unique gifts that sailing affords than I believe could ever get from simply pushing a button on a GPS. 

Don't get me wrong I have pushed more than my fair share of buttons   

Do what you makes comfortable and increases your sense of security and confidence because that is what will help you over the horizon or across the bay. How you do it is often times less important simply doing it.

Just my .02 cents.


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## rockDAWG (Sep 6, 2006)

Not try to change the topic here. 

If you need to ditch you SV and climb up to the life raft. Beside the other essentials, what would you rather take, GPS with spare battery or your sextant charts, calculator and etc.

Let here from the both sides.


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## btrayfors (Aug 25, 2006)

rockDAWG said:


> Not try to change the topic here.
> 
> If you need to ditch you SV and climb up to the life raft. Beside the other essentials, what would you rather take, GPS with spare battery or your sextant charts, calculator and etc.
> 
> Let here from the both sides.


Neither. I'd clutch my EPIRB with a death-grip  With or without GPS (the built-in 121.5mhz beacon will pinpoint you when help arrives).

Without this and with a fully functioning portable GPS, at least you'll know your own position with certainty when you die of thirst or starvation!

Bill


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## ffiill (Jul 15, 2010)

Mid day sun sights are easy-then all you do is use a sight reduction table and proformat sheet into which you put the numbers and do some simple adding and subtracting.
Of course the most fun is dead reckoning plus a sighting line and stick-the Polynesians got to NZ that way and across the south Pacific.One you have got the angle marked up the next person who wants to find you just sails either north or south until they get the same angle ;placing them on the same longtitude;then east or west to reach you.
I have a couple of GPs s as well and the astro calculator from Pangolin


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## AdamLein (Nov 6, 2007)

rockDAWG said:


> If you need to ditch you SV and climb up to the life raft. Beside the other essentials, what would you rather take, GPS with spare battery or your sextant charts, calculator and etc.


I'm assuming this thought experiment is taking place far enough from land and popular routes that you expect to be drifting for a while.

You don't need charts to use a sextant. You need to know the sun's declination, which you can compute on your calculator of choice. But that's besides the point; would you really consider not taking charts with you when you abandon your vessel? At the very least you should have pilot charts so you can keep track of the currents.

Personally my handheld is usually in a jacket pocket if I'm not using at the moment, so if I'm grabbing navigation devices, it comes along for free.


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## jackdale (Dec 1, 2008)

AdamLein said:


> Personally my handheld is usually in a jacket pocket if I'm not using at the moment, so if I'm grabbing navigation devices, it comes along for free.


My ACR Aqualink PLB is with me at all times offshore.

The grab bag contents vary; long passage versus 50-100 miles offshore. But a GPS is a waterproof bag is one requirement along with a VHF in a waterproof bag.


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## cb32863 (Oct 5, 2009)

It still befuddles me the "anti" attitude towards learning celestial nav. Both here and on AS. I find it intersting to learn and folks were getting around just fine for a few hundred years, if not more, with it. As the only way to nav thses days, no, of course not but, why not learn it if you want to. If you see no need then don't and you really shouldn't discourage others from doing so.

My 2 cents.


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## Omatako (Sep 14, 2003)

btrayfors said:


> Neither. I'd clutch my EPIRB with a death-grip  With or without GPS (the built-in 121.5mhz beacon will pinpoint you when help arrives).
> 
> Without this and with a fully functioning portable GPS, at least you'll know your own position with certainty when you die of thirst or starvation!
> 
> Bill


No question about the EPIRB if you have one. But the GPS in concert with the portable VHF that we all carry in our grab bags  allows the searching vessel pottering around on the horizon to find you much easier.



AdamLein said:


> You don't need charts to use a sextant. You need to know the sun's declination, which you can compute on your calculator of choice. But that's besides the point;


Agreed. Following on from Bill's thoughts above, with celestial gear in the life-raft you will have only a vague idea of where you are when you die of thirst and starvation.



AdamLein said:


> which might be a good idea, so that you aren't all rusty at finding call boxes once The Man or The Sun or Zeus or whoever comes and shuts down your satellite phone. Assuming you're concerned about that.


Maybe it's different where you live but where I live finding a call box would be serious challenge, almost an impossibility.



cb32863 said:


> It still befuddles me the "anti" attitude towards learning celestial nav.


Actually I thought the majority of posts here were positive towards learning and using celestial nav. The pure reality though is that the vast majority of recreational/cruising sailors today use it for recreation if at all. Bottom line is I can buy several GPS units for the cost of a good sextant and whilst it is true that a GPS can let you down, stumbling on a heaving deck and dropping/banging a sextant and rendering it useless is also not beyond the realm of possibility. In addition, sight reduction tables are expensive as are nautical almanacs which should be replaced annually. Most cruising sailors these days would rather avoid this expense. And in any case for coastal navigation, the sextant and its associated paraphanalia is academic.



cb32863 said:


> Of course the most fun is dead reckoning plus a sighting line and stick-the Polynesians got to NZ that way and across the south Pacific.


Much like the pioneers crossed America in tented wagons . . . . but they don't anymore.

Excuse me, I'm just having fun, I don't pooh-pooh the use of celestial nav, I think it's a lot of fun and we often take sights and plot position lines and fixes when we're at sea. But the really fun part is checking the GPS to see how close we got.


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## Slayer (Jul 28, 2006)

When I was in Hawaii I read that the Polynesians would lay in their boats and feel the waves to estimate their location. I think they did it in conjunction with celesitial navigation, but it still is pretty amazing.


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## genieskip (Jan 1, 2008)

One point that needs to be made is that if all the electronics on the boat go belly up your sextant might not be much help because the third requirement for celestial navigation (after a sextant and sight reduction tables or a nav calculator) is accurate time. Very few, if any, cruising sailors have a calibrated chronometer, one which has been monitored carefully so that the error is known and can be corrected for, to fall back on. 

Almost all celestial navigators I have sailed with, myself included, use a radio time tick to set a stopwatch to get an accurate time on their sights. No radio = no accurate time = one line of position each day at noon of your Latitude - if a cloud doesn't obscure sun at just the right moment. Better than nothing, but far from ideal. If you get hit by lighting, as happened to me on a Bermuda-Halifax many years ago, and all the electronics get fried you are in deep doodoo. We had a good recent fix and weren't that far from land so we were able to stumble our way in by Dead Reckoning but it wasn't easy and I was glad we had a really good navigator aboard.

So you need to keep in mind - if you want to have a sextant aboard by all means do so and learn to use it, but remember it isn't much help without accurate time.


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## btrayfors (Aug 25, 2006)

Genieskip,

Very good point.

However, as you point out, you can get an LOP for your latitude each day even without accurate time. 

Moreover, most everyone has a good quartz watch these days. If you are reasonably prudent, this can serve very well. Don't forget, an error of 4 seconds = 1 nautical mile, so even an error of a minute or so only results in an error of 15 nautical miles. In many instances, that would be sufficient.

It would also afford a good opportunity to "run down your latitude".

BTW, I give a "time tick" on the WaterWay Net (7268 kHz LSB daily @ 0745 Eastern time) whenever I'm net control, just in case anyone really cares about time accuracy 

Bill
WA6CCA


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## rockDAWG (Sep 6, 2006)

Without an apparent answer, I come to the conclusion that if you can only to either GPS or Sextant, all would take a GPS. However, I am sure there a few whose balls are all hair will take the sextant. All power to you.


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## TQA (Apr 4, 2009)

genieskip said:


> One point that needs to be made is that if all the electronics on the boat go belly up your sextant might not be much help because the third requirement for celestial navigation (after a sextant and sight reduction tables or a nav calculator) is accurate time. Very few, if any, cruising sailors have a calibrated chronometer, one which has been monitored carefully so that the error is known and can be corrected for, to fall back on.
> 
> 
> 
> ...


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## Nitro (Feb 4, 2009)

Have to agree that for 99.5% of sailors, there is no practical need for a sextant in 2011. But then again, if we were simply trying to get from point A to point B, we wouldn't sail to do it. 

I own a C-Plath. Seldom use it. But it gives me comfort that if I need it, I have it. And IMHO, given the intense spirituality of an offshore voyage/race at night, connecting with the constellations I'm flying through makes it that much deeper.


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## schwartzli (Jan 16, 2011)

There are only 24 GPS satellites in orbit, not "hundreds". You need signals from at least three satellites for a fix. Four to five is better.

I use an Android phone with Google Maps running off the phone's GPS. I have lost the GPS signal numerous times while driving to work, often in the rain for extended periods. It's not much of a problem on I-95, but I'd be pretty put off if it happened in the middle of Long Island Sound, forget about off the coast. 

We had a kind of GPS "blackout" three years ago. The Long Island Rail Road uses GPS in its train cars to determine position. Something related to the GPS network changed, and the whole destination sign/announcement system went on the fritz. Each train car -- the entire fleet -- had to be individually reprogrammed in the shop. ALL the destination signs, AND the automated on--board announcements, were turned off, and reactivated one car (pair) at a time over several months. 

I'd recommend always having a backup in case you lose GPS capability offshore.


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## Omatako (Sep 14, 2003)

schwartzli said:


> There are only 24 GPS satellites in orbit, not "hundreds". You need signals from at least three satellites for a fix. Four to five is better.


Actually there are 31 . . . .

From Wikipeadiea . . . . . . "As of March 2008, there are 31 actively broadcasting satellites in the GPS constellation, and two older, retired from active service satellites kept in the constellation as orbital spares."

My simple little hand held almost always finds 8 or 9 sats so we would have to lose 5 or more for the system to "go down". I can't remember an occasion in which I had no GPS at any time.


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## justified (Jun 14, 2007)

Back to the OP's original question 
What books? I found this one and it makes for an easy read and it give you an understanding of the basic concepts "Celestial Navigation for the Clueless".
I do love the banter on this site that comes to almost every post! 
Peter
s/v Frayed


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## ffiill (Jul 15, 2010)

I just use a sextant for the fun of it.
By the way it is possible to work out longtitude without reference to GMT/UT.
Cook used system along side some of the first accurate marine chronometers.
Its all to do with star and planet plots enabling you to get a 2 d fix same way that satellites do it for you-very complex maths and not that accurate.
As for accurate clocks Slocum back in 1900s and Francis Chichester (of single handed around the world sailing fame)in 1930s in his aeroplane used tinplate alarm clocks.
It has to be said that my Great Uncles pocket watch circa 1900 can be more accurate than my digital Casio watch!
As for satnav when I bought my first Magellan handheld back in 1994 it clearly stated in the manual that the US government reserved the right to switch off the system as and when it felt the need.
I am guessing such a time might have been 9/11 when clearly it was very useful to terrorists.
I can also guarantee that submarines jam it for obvious reasons when coming to the surface-a regular occurence on the Firth of Clyde where I once lived when Trident Missile subs returned off their nuclear deterent patrols!
As they passed by your GPS would go haywire!


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## Kiltmadoc (Nov 10, 2009)

FWIW: the GPS that we all rely on is not always reliable. The FAA just sent me a notice that they finally got the WAAS satellite working again after a 3 MONTH outage (i used to fly regularly, so I am still on their notification list). Now, a boat doesn't need WAAS, but it's still sobering to realize that with all those satellites, things can still go wrong. I am personally interested in knowing how to do celestial navigation for the same reasons that I still carry a compass when backpacking...you never know when the batteries will run out or an errant splash ruins your gear.


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## AdamLein (Nov 6, 2007)

justified said:


> Back to the OP's original question
> What books?


Bowditch has instructions on drawing horizon diagrams, which are awesome and take *all* the math and all of the tables out of sight reduction (and are not accurate below one degree, heh). I haven't seen these instruction's elsewhere, though I understand the Dalton book has them as well. If you're doing CN for fun and you like geometry or drawing pictures, or you think minimizing your use of electronics is fun, you should definitely pick up this skill.

In any case people say Bowditch is heavy reading but I don't see the problem. It reads like a textbook, that's all. Everything is built from the ground up. It also has the benefit of teaching you all the navigation you actually "need" to know; you really only need one book.


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## T34C (Sep 14, 2006)

Kiltmadoc said:


> FWIW: the GPS that we all rely on is not always reliable. The FAA just sent me a notice that they finally got the WAAS satellite working again after a 3 MONTH outage (i used to fly regularly, so I am still on their notification list). Now, a boat doesn't need WAAS, but it's still sobering to realize that with all those satellites, things can still go wrong. I am personally interested in knowing how to do celestial navigation for the same reasons that I still carry a compass when backpacking...you never know when the batteries will run out or an errant splash ruins your gear.


Even without WAAS your GPS was faaaaaar more accurate than any CN fix you are going to get.

I don't understand the argument that your batteries could go dead on your GPS, but you are willing to drag a big sextant around in its box. (?) If you can drag that thing around, why can't you take some extra batteries?


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## AdamLein (Nov 6, 2007)

T34C said:


> If you can drag that thing around, why can't you take some extra batteries?


Because it is _beautiful_ whereas batteries are _ugly_.


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## T34C (Sep 14, 2006)

AdamLein said:


> Because it is _beautiful_ whereas batteries are _ugly_.


Maybe, but I measured and found I can get 180 AA batteries (in their packaging) into the same space as my cheapy sextant. Conservatively, that gives me 1,800 hours of run time on my backup GPS that get me more accurate location information, faster, easier, and cheaper than any sextant.


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## sailingdog (Mar 19, 2006)

And a lightning strike turns all those batteries into deadweight when the GPS gets fried... but the sextant would still work. 



T34C said:


> Maybe, but I measured and found I can get 180 AA batteries (in their packaging) into the same space as my cheapy sextant. Conservatively, that gives me 1,800 hours of run time on my backup GPS that get me more accurate location information, faster, easier, and cheaper than any sextant.


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## T34C (Sep 14, 2006)

sailingdog said:


> And a lightning strike turns all those batteries into deadweight when the GPS gets fried... but the sextant would still work.


...and good luck using it without your calculator!


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## AdamLein (Nov 6, 2007)

T34C said:


> ...and good luck using it without your calculator!/QUOTE]
> 
> My slide-rule is lightning-proof. Unless it gets struck directly, then I'm not sure what would happen. I guess at least the ink would melt or burn or explode.
> 
> ...


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## rockDAWG (Sep 6, 2006)

If such misfortunes fall upon me - lightning strike kills all my electronics, kills all backup GPS (including those are not on), burns my sails, and exposes all my batteries, I will be happily prepare my death after I finish my food, water and all the liquor on board. There is no sense to waster and no need to fight, I will depart peacefully.


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## sailingdog (Mar 19, 2006)

T34C said:


> ...and good luck using it without your calculator!


Unlike you, I can read sight reduction tables without the need for a calculator.


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## acunningham (Nov 25, 2010)

sailingdog said:


> And a lightning strike turns all those batteries into deadweight when the GPS gets fried... but the sextant would still work.


I'm extremely sceptical that a lightning strike could damage AA batteries that aren't in an electronic device. When not in use, they're fundamentally chemical rather than electrical, and no more susceptible to lightning than any other chemical on board.

Do you have any real-world examples of this happening?


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## RedtheBear (Sep 14, 2010)

Being a firm believer in poor sod's laws, the fickel finger of fate and whatever can and almost certainly will go wrong; I carry two extra anchors, pencils, note pads, a set of tables and a quartz water resistant watch. MY CN may not get used except to show the grandchildren how they used to do it, BUt it can be done. Sure I might be off several miles but I usually can see much further than that and as they say "Close enough to smell". CN is not that hard to get the basics and then it's practice. Gee, I guess they quit teaching Spherical Trig in high school. Been a long time ago, probably about the time they quit teaching how to add, subtract, multiply and divide with you brain and not a machine! CN is a tool, a skill, usful just like sail mending and splicing, not required but sure handy.
And thats the 'ol bear's' 2 cents worth.


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## AdamLein (Nov 6, 2007)

As SD would say, _I should point out that_ if there's a zombie apocalypse, it's likely that the control segment (on the ground) would eventually be overrun or shut down due to inadequate energy. GPS signals would soon become erroneous as satellite orbits would not be corrected, etc.

(Also note: you CNers had better print out now all the tables you'll ever need... just in case).

Replace zombies with your favorite end-times scenario.


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## Classic30 (Aug 29, 2007)

acunningham said:


> I'm extremely sceptical that a lightning strike could damage AA batteries that aren't in an electronic device. When not in use, they're fundamentally chemical rather than electrical, and no more susceptible to lightning than any other chemical on board.
> 
> Do you have any real-world examples of this happening?


Perhaps he could have expressed it differently, but I think the Doggie's point was that if the GPS is toast, the batteries that go into it aren't much use any more..


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## acunningham (Nov 25, 2010)

Hartley18 said:


> I think the Doggie's point was that if the GPS is toast, the batteries that go into it aren't much use any more..


Sorry, my mistake. You and Doggie are quite right.


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## Omatako (Sep 14, 2003)

Kiltmadoc said:


> FWIW: the GPS that we all rely on is not always reliable. The FAA just sent me a notice that they finally got the WAAS satellite working again after a 3 MONTH outage (i used to fly regularly, so I am still on their notification list). Now, a boat doesn't need WAAS, but it's still sobering to realize that with all those satellites, things can still go wrong. I am personally interested in knowing how to do celestial navigation for the same reasons that I still carry a compass when backpacking...you never know when the batteries will run out or an errant splash ruins your gear.


Actually if I'm not mistaken WAAS is only available on continental USA, is a terrestrial system (not satellite) and when available is accurate to a metre or less? Whatever, it's not available in 90% of the sailing world so in the bigger picture it's availability is academic.

Oh and besides another comment that batteries take far less space than a sextant, my GPS (and I'm sure most others too) runs very well off the boat's system power (no batteries required) and is TOTALLY waterproof. And it's far more resistant to bumps and drops than a sextant.

But go for CN, it's worth it if you have the desire.


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## thekeip (Aug 8, 2007)

many years ago, early 70's I think, my wife and i took all the USPS courses, including JN & N...(Barnagat Bay PS) what a hoot. Hours and hours of just pure, unadulterated pleasure, especially the voyage from Pt. Judith Light to Bermuda. So we took the exams, did very well, she actually got a better mark than I. She was the only woman in the class for the two years it took to do the N classes. Anyway, I got a nice plaque in recognition of the achievement, she didn't. Neither of us has had anything to do with USPS since then. Regardless, the instruction was absolutely 1st rate.
Go for a good USPS program if you can...it's just marvelous.


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## JKCatalina310 (Nov 18, 2010)

*This post is just getting absurd*

I would actually expect this type of resistance to CN on a power boat forum but not on a sailboat forum.

I guess this is just a sign of the times that some people don't want to put in the time to learn the appropriate things before going out on the sea. Do any of you who are against CN at least know how to perform dead reckoning?

For that matter, why take a boaters safety coarse or learn basic seaman ship? After all, the coast guard is there to rescue you, right?



Omatako said:


> Oh and besides another comment that batteries take far less space than a sextant, my GPS (and I'm sure most others too) runs very well off the boat's system power (no batteries required) and is TOTALLY waterproof. And it's far more resistant to bumps and drops than a sextant.


I think the whole point of learning CN is that boat power systems are notoriously unreliable and can go out at anytime without notice. So relying on your "built in" GPS may actually be the worst decision of all. (By the way, anyone who says something, anything, is "TOTALLY waterproof, just hasn't spent enough time on the water, IMO.)

Don't get me wrong, GPS is a great tool, it gives a great check to your other navigation skills. (I love my Garmin 76Cx and spent all last night laying out potential cruising routes for this summer on my computer to download onto my GPS.) But it is not the end-all be-all in navigation.

I have been caught in the fog a few times. The worst I can remember was when we were out watching the start of the Volvo Ocean Race leg that went from Boston to Ireland. The fog was so bad that one of the race boats almost hit a barge coming into Boston Harbor. If I didn't have the GPS to check my dead reckoning I would have been nervous as hell. Even with the GPS is was scary because we couldn't even see a bridge we were traveling under. We had the GPS, VHF on 16, compasses (the built in and hand bearing), charts and signal horn all going to ensure safe passage home.

The whole time on the way back, we heard a power boater talking to the CG. He was lost in the fog. His on board "TOTALLY waterproof" GPS had failed. His backup hand held GPS wouldn't work and he couldn't even relay his last known position to the CG because he didn't know how to read a chart well. We were safe back at our slip for 2 hours before the CG finally found him. And we even took a couple of loops to look for him because the area he was describing where he was fishing was near our location. When they finally found him, he was more then 2 miles from the area he described.

To me, the bottom line is that you have to plan as if you are out there entirely on your own. If you feel comfortable with just a GPS, so be it. But you should have to reimburse the CG for the rescue effort if you need assistance, IMO.


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## T34C (Sep 14, 2006)

sailingdog said:


> Unlike you, I can read sight reduction tables without the need for a calculator.


You can read!!!!??????


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## T34C (Sep 14, 2006)

JKCatalina310 said:


> I would actually expect this type of resistance to CN on a power boat forum but not on a sailboat forum.
> 
> I guess this is just a sign of the times that some people don't want to put in the time to learn the appropriate things before going out on the sea. Do any of you who are against CN at least know how to perform dead reckoning?
> 
> ...


I hope to God you are kidding. DR has absolutely nothing to do with celestial navigation, nor is it exclusive to star gazing. Using good navigation is something you should be doing if you are using a GPS or CN. Using a GPS only replaces using a sextant, not good seamanship. What you describe is a powerboat that was being totally reliant on his chartplotter, an extension of GPS. Using a chartplotter as your sole means of navigation is a completely different discussion.

The discussion of the how many batteries fits into the space of a sextant is relevant in that most people will (at least claim) that they carry a sextant as a back-up to their GPS in case the sky starts falling. My point was that they would be far better served carrying extra batteries than carrying a sextant.


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## travlin-easy (Dec 24, 2010)

Nearly ALL GPS units are completely waterproof. In fact, most console mounted systems are submersible to depths of up to 100 feet. Some handhelds claim they are water resistant, but a few claim they're submersible as well. Hummingbird, for example, is often displayed running a simulator while in an aquarium at the boat and outdoor shows. Add to this a host of wonderful features such as: Anchor Alarm, off-course alarm, built-in charts, new supertwist sunlight viewable displays, HD displays, trails, pin-point repeatable accuracy, built in depth/fish finder, multiple instrument display, auto-pilot interface system, massive waypoint storage and rugged construction. 

That said, I'm not against CS--it's a last-gasp backup system that will work if all else fails. Of course, that's if the sky is clear and the weather is relatively calm. All bets are off on a rainy, snotty night in the middle reaches of Chesapeake or Delaware bays. Under these circumstances I'll stick with the GPS and compass as my primary sources of navigation, and for a backup I have a spare, handheld GPS--just in case.

Cheers,

Gary


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## JKCatalina310 (Nov 18, 2010)

T34C said:


> I hope to God you are kidding. DR has absolutely nothing to do with celestial navigation, nor is it exclusive to star gazing. Using good navigation is something you should be doing if you are using a GPS or CN. Using a GPS only replaces using a sextant, not good seamanship. What you describe is a powerboat that was being totally reliant on his chartplotter, an extension of GPS. Using a chartplotter as your sole means of navigation is a completely different discussion.
> 
> The discussion of the how many batteries fits into the space of a sextant is relevant in that most people will (at least claim) that they carry a sextant as a back-up to their GPS in case the sky starts falling. My point was that they would be far better served carrying extra batteries than carrying a sextant.


The only relationship to DR and CN is that they are both navigation tools, just like a GPS. What I asked was that if the people who are against CN knew how to DR getting at that some are just totally reliant on GPS/chartplotters. This line you are objecting to was mainly in jest and was hyperbole in trying to make my point.

As sailors, we often set to sea with many redundant, distinct backup systems. So that if one fails we have many options to get to a safe place. An example of this is through-hulls. A well prepared boat has a TH, seacock, backup/replacement hoses, TH & SC, and many of us carry plugs and underwater setting epoxy. If a hose connected to a TH fails, we can shut the SC and replace the hose with the backup. If the SC fails, we can plug the TH and then affect a repair with the other backup materials we carry.

In the above example, the extra batteries are like carrying the extra hose. Without the SC or the plug (or both) you are not properly prepared, IMHO. You need a separate, redundant system i.e. the sextant. Your extra battery argument only works if you believe the only thing that can go wrong with a GPS is that you use up the power. What about electrical failure, what about falling overboard, etc.?

However, we all know many sailors and power boaters who go to sea without many of these things that most of us consider necessary for a well prepared boat. Most of the time, they don't have an issue. So again, I believe it is a personal choice. Just that talking about carrying 180 batteries as a better backup to a sextant is just absurd. For one, it takes no account for weight. My Davis Mark III sextant (cheap plastic beginner sextant) maybe weighs a 1/2 pound. How much would 180 batteries weigh?

By the way, I will be carrying the following as navigation tools and backup on my C310 (I am sure some think this is overkill): fixed compass, fix GPS/chart plotter/radar, hand-bearing compass; hand held GPS/chart plotter with extra batteries (usually an 12 pack), sextant, dividers and other navigation tools, log book and two sets of paper charts. I carried most of this on my C&C 24 but I didn't have some of the fixed items.


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## svs3 (Jun 23, 2006)

GPS and CN are simply tools to get a specific job done. It is not a question of which one is better. The real issue is skill of the user. I'd take a skilled celestial navigator over an unskilled electronic navigator any day. At the end of the day, it is really about whether or not you have any confidence in your fix not how you arrived at your fix.

A good navigator will take any and all meaningful inputs available to get as good a fix as possible. This requires always making sure the details fit the big picture and that big picture fits the details.

IMHO, being skilled at ALL forms of navigation (or as many as possible) is both good and desirable and will only increase one's self-sufficiency and independence.

For those interested, the introductory chapters of Calder's How To Read A Nautical Chart provides an good discussion about some of the issues to be aware of with regard to electronic navigation.


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## AdamLein (Nov 6, 2007)

travlineasy said:


> That said, I'm not against CS--it's a last-gasp backup system that will work if all else fails. Of course, that's if the sky is clear and the weather is relatively calm. All bets are off on a rainy, snotty night in the middle reaches of Chesapeake or Delaware bays. Under these circumstances I'll stick with the GPS and compass as my primary sources of navigation, and for a backup I have a spare, handheld GPS--just in case.


That's another aspect that has not been discussed. If you didn't have that GPS, you would be a lot more cautious and would stay the hell away from shore on a rainy snotty night (though, in the middle of the Chesapeake or Delaware Bays, CN is not really the appropriate navigational tool anyway).

Over-reliance on any manner of newfangled gadgetry can (not in all mariners I'm sure) open the door to less prudent planning and decision making, and more risk taking. Like motoring too close to shore with your sails covered, or using a chartplotter to the exclusion of paper charts, cell phones instead of VHF, etc. Not saying we all do this, but we're all much more likely to play it safe if we are forced to rely on low-tech, high-skill systems.

This is why, while I have a GPS and know how to use it (and even consult it while sailing), I try to do most of my navigation by paper chart and hand-bearing compass. If you're into sailing because you like the idea of being self-reliant, low-tech navigation is important to practice, regardless of how many batteries you can carry.


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## JKCatalina310 (Nov 18, 2010)

AdamLein said:


> If you're into sailing because you like the idea of being self-reliant, low-tech navigation is important to practice, regardless of how many batteries you can carry.


Well said!


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## travlin-easy (Dec 24, 2010)

Low tech navigation is how many of us old farts learned to navigate--which in my case was more than a half-century ago. Most of the time I found my way back home, often after a day's fishing 50 to 70 miles offshore. Back then we had a compass and charts. There were times, though, when we were damned well lost and dead reconing was the only option. That, along with pure, dumb luck.

Then along came RDF. WOW! What a wonderful advancement in navigation. We could home in on a radio station, which was listed on our charts, establish a course, and by golly we were able to run directly to the inlet. It worked pretty darned good unless there were thundershowers in the vicinity.

When I was about 17, I joined the U.S. Navy. Back then (1957) Loran A was considered High-Tech gear. It was a massive unit that took forever to stabilize, but when it did, the accuracy was incredible. Again, it was great unless there were thundershowers in the vicinity, at which point it lost its low frequency AM signal.

Loran C replaced Loran A, and while miniaturization of electronic components solved many of the problems and improved the unit's speed and accuracy, it still had problems with thundershower static that would kill the signal and make navigating with Loran an impossible task.

When the first GPS systems were available to the general public, they were large, unwieldy, required a degree in computer programming to operate and very, very expensive. How things have changed. Now, they're relatively inexpensive, compact, operate under intolerable weather conditions, and they're extremely reliable. About the only problem anyone usually encounters is total power failure, which is quite rare. Most boats have more than a single battery, and in my case, there are six of them--four of which are dedicated for house power, and a pair of deep-cycle, heavy duty batteries dedicated for engine use. Additionally, there's a solar charging system that keeps all of them fully charged and a battery monitoring system that tells me the state of each battery at any given time.

The last time I used a sextant, which was about two years ago, I decided to put it in its case and store it safely in a cushioned compartment. I only took it out back then to make sure I remembered how it worked. Even at my advanced age I can still use my eyes, charts, compass and binoculars to find my way around Chesapeake Bay during the day. At night, however, the GPS is MY primary method of ACCURATE navigation. The repeatable accuracy is +/- 9-feet, which is as close as anyone needs to be. (at times it's better.)

The beauty of navigating at night with the GPS is I don't have to worry about overcast, cloudy conditions and I can get the heck out of the commercial shipping lanes, which can be very dangerous at night. Between heavy barge traffic, tugs, freighters, tankers, Naval vessels, and dredge-barges, the channel can be a bad place to be on an ink-black, cloudy night.

As the saying goes--"Whatever floats your boat!"

Gary


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## Omatako (Sep 14, 2003)

*Absurd indeed and getting more so . . .*



JKCatalina310 said:


> I would actually expect this type of resistance to CN on a power boat forum but not on a sailboat forum.


Once again, I don't see a whole lot of resistance - most posts agree that CN is an OK skill to have and use. However, the common opinion is that GPS is better and for coastal or inland navigation, which is what 80% of the members of this board are into, CN is simply no substitute for GPS.



JKCatalina310 said:


> I think the whole point of learning CN is that boat power systems are notoriously unreliable and can go out at anytime without notice. So relying on your "built in" GPS may actually be the worst decision of all.


Perhaps that was a generic assumption but if aimed at me then you missed the fact that I don't own a "built in" GPS, I only have hand-held. As far as boat power systems being unreliable and going out, well, I'm not sure about that. Mine has been super reliable and long may that continue.

And you appear to have missed the point that even a light bump or fall can instantly turn a sextant into an ornament. So how many people carry three sextants for redundancy? Not many, I'll wager.



JKCatalina310 said:


> (By the way, anyone who says something, anything, is "TOTALLY waterproof, just hasn't spent enough time on the water, IMO.)


How about 36000nm of ocean crossings, 19000nm of them using the same handheld GPS which is still, believe it or not, waterproof. And also by the way, the failure of the "totally waterproof" GPS that belonged to the power boater you referred to probably had nothing to do with water ingress but I concede, we don't know that. And I know lots of things that are totally waterproof.


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## hellosailor (Apr 11, 2006)

"Actually if I'm not mistaken WAAS is only available on continental USA, is a terrestrial system (not satellite) and when available is accurate to a metre or less? Whatever, it's not available in 90% of the sailing world so in the bigger picture it's availability is academic."
IIRC WAAS uses two ground stations, one on each coast of the US, at present. It doesn't give you meter accuracy, but rather it takes the typical 10-meter accuracy down to 3-meter. I say "typical" because accuracy is a moving target, sometimes quoted at the 95%-performance number, others times at other numbers (i.e. accuracy at more or less than 95% of the time) and that's a whole technical debate in itself.
I consider GPS to be good within about 1/2 mile at best and at that point, I want to be relying on piloting and other ground conformation before I place any higher confidence in the numbers. Because I know that the numbers are right, but MAPS in general aren't so precisely and accurately drawn.
I know, the GPS is often within five or ten meters. And also, often 1/2 mile or further off when compared to maps or charts.

When the _navigator _gets broken, any idiot on the boat can use the GPS. Odds are no one else will be able to use the sextant as reliably or quickly. So, yeah, sure, the GPS is a frail thing relying on electronics and the sextant is real robust. And esoteric and beyond the use of the entire crew unless they're all celestial navigators.

So let's forget whether GPS or sextant is the more fragile system, they both can be easily trashed.


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## RedtheBear (Sep 14, 2010)

the ol' bear with his two cents worth again:
The first and best nav tool is the one between you ears!!! Just as the steam engine, loran, and GPS, the are all tools for the sailor to use to do what he needs to do. He uses them as they are avalible to use to the best of his ability. If the latest tec gadget is avalible and works of course he uses it, if not then he takes a step back and uses the next best thing he has. All we are saying is that many of us want every step in the ladder we can have.
The self relient, never guit, I can do it myself aditude that is second nature to the wind sailor wants every tool is his bag he can get. Give up my GPS, only when the batteries are dead and the sky is falling, but I'll still have my sextant, and when I drop it, my angle stick, and when it breaks, the bunp on my head that says North is that way.


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## Flybyknight (Nov 5, 2005)

RedtheBear said:


> the ol' bear with his two cents worth again:
> The first and best nav tool is the one between you ears!!! Just as the steam engine, loran, and GPS, the are all tools for the sailor to use to do what he needs to do. He uses them as they are avalible to use to the best of his ability. If the latest tec gadget is avalible and works of course he uses it, if not then he takes a step back and uses the next best thing he has. All we are saying is that many of us want every step in the ladder we can have.
> The self relient, never guit, I can do it myself aditude that is second nature to the wind sailor wants every tool is his bag he can get. Give up my GPS, only when the batteries are dead and the sky is falling, but I'll still have my sextant, and when I drop it, my angle stick, and when it breaks, the bunp on my head that says North is that way.


Now there's a man after my own heart, except I try to use my gps only as a check _after_ DR and or CN.

Dick


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## travlin-easy (Dec 24, 2010)

There seems to be some misconceptions about the accuracy of GPS and their associated chart plotter systems. My navigational experience with GPS has been limited to eastern U.S. Coastal waters out to 100 miles, mainly in an area from northern New Jersey south to the Marquesses Keys. The vast majority of the time the GPS accuracy was approximately 9 feet (3 meters). I've used it on many occasions to return to a buoyed anchor, which was dropped off the boat so we could chase monster bluefin tuna and billfish--often for distances of 10 or more miles. Every time we did this we marked the anchor buoy as a waypoint and were able to easily find the buoy in pitch, black darkness.

Damaging a GPS, especially one that is console mounted, is next to impossible. Sure, you could drop your boom on it, but that's an unlikely scenario. The shock of a sailboat pounding through towering seas is nothing compared to the bone-jarring ride of a bass boat on a choppy lake, or a center-console fishing boat slamming into 8-foot waves while heading offshore for a day of tuna chunking. Believe me when I say your spine will fall apart long before that GPS does.

You can find all the information you need on GPS systems and their accuracy at Garmin | What is WAAS? .

Cheers,

Gary


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## Boasun (Feb 10, 2007)

The only attachment for my sextant that I really want, is a Cloud splitter. That way I can get my sun & stars on overcast days. 
In the mean time I will have to use my Norse sun stone to determine the direction of the sun.


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## AdamLein (Nov 6, 2007)

Boasun said:


> The only attachment for my sextant that I really want, is a Cloud splitter. That way I can get my sun & stars on overcast days.
> In the mean time I will have to use my Norse sun stone to determine the direction of the sun.


It all sounds highly probable.


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## Classic30 (Aug 29, 2007)

travlineasy said:


> Damaging a GPS, especially one that is console mounted, is next to impossible. Sure, you could drop your boom on it, but that's an unlikely scenario. The shock of a sailboat pounding through towering seas is nothing compared to the bone-jarring ride of a bass boat on a choppy lake, or a center-console fishing boat slamming into 8-foot waves while heading offshore for a day of tuna chunking. Believe me when I say your spine will fall apart long before that GPS does.


I would not agree with that assessment for one second.

eg. I have a Navman Tracker 5430i (internal antenna) chartplotter that, according to many here, I'm supposed to be able to rely on whilst navigating my way around. It has a few issues:
1. The manual states it could take a minute or two on a good day, but I've only managed to get satellite lock about 1-in-4 times I've turned the thing on (in the cockpit in clear view of the sky).
2. The screen can't be viewed in bright sunlight - and if you CAN see it, you'd better have good glasses..
3. The buttons must come out of the cheapest factory in China, since they'll often get stuck down and/or not register at all, due to internal corrosion and/or crappy manufacture.

Shock is the least of the problems.. it seems that nowadays all these things are made to a price and their ability to withstand the marine environment outside of the warranty period is doubtful at best.

On the other hand, the Furuno GPS (a GPS only unit) with external antenna installed on my Dad's boat is fast, simple and reliable - assuming you have a paper chart nearby to mark your position..


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## travlin-easy (Dec 24, 2010)

Sounds as if the Navman is a real junker. My Lowrance LMS-332 locks up the satellites in less than 10 seconds upon startup, it has a supertwist LCD screen that can be read in direct sunlight, the charts are extremely accurate, you can add and save locations of buoys that have been moved, such as those in the Havre de Grace, Maryland channel, and the buttons are outstanding after several thousand pushes. Mine has been inadvertently kicked while coming from the cabin deck to the cockpit, endured torrential rains, bone chilling cold and scorching heat and never missed a beat. It has an external antenna that is attached to a safety rail near the stern, the antenna is quite small, out of the way, and has never had a single drop-out in more than 4 years of use. They're made in Tulsa, OK, but I'm sure most of the parts are made in China, which is where most of the higher quality electronic gear seems to come from these days.

Bottom line: After reading about your experiences, you may want to consider switching to a more reliable machine.

Good Luck,

Gary


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## Classic30 (Aug 29, 2007)

travlineasy said:


> Bottom line: After reading about your experiences, you may want to consider switching to a more reliable machine.


Yep. Will be... and probably not another stupid chartplotter either. My phone does a better job! 

..but the lesson remains that with all nav equipment from sextants to EPIRBS, if you're serious about the safety of yourself and your crew, don't be tempted to skimp on quality - in whatever form that takes. 

Cheers,
Cameron


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## dillybar (Nov 10, 2009)

Boasun said:


> The only attachment for my sextant that I really want, is a Cloud splitter. That way I can get my sun & stars on overcast days.
> In the mean time I will have to use my Norse sun stone to determine the direction of the sun.


There's an app for that!! If you have an I Phone and 4.99 you can download something called "GoSkyWatch". It turns your phone into an electronic star chart that will show you the exact Alt. and Z at any given moment for any object in the sky (or below it) simply by pointing at it. Clear sky or horizon not needed.
It will also give you the objects rise, set and transit as well as brightness, color and orbit stats for planets etc.
So once you have the Alt., Z and exact time from your phone you can
consult your almanac and do a few calculations and in 10 minutes or so presto, you have your location! 
Or I suppose you could by pass all that and just hit the GPS icon


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## sailingdog (Mar 19, 2006)

Cool. Google Sky Map is pretty nice, but doesn't have that ability AFAIK.



dillybar said:


> There's an app for that!! If you have an I Phone and 4.99 you can download something called "GoSkyWatch". It turns your phone into an electronic star chart that will show you the exact Alt. and Z at any given moment for any object in the sky (or below it) simply by pointing at it. Clear sky or horizon not needed.
> It will also give you the objects rise, set and transit as well as brightness, color and orbit stats for planets etc.
> So once you have the Alt., Z and exact time from your phone you can
> consult your almanac and do a few calculations and in 10 minutes or so presto, you have your location!
> Or I suppose you could by pass all that and just hit the GPS icon


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## travlin-easy (Dec 24, 2010)

Hartley18 said:


> Yep. Will be... and probably not another stupid chartplotter either. My phone does a better job!
> 
> ..but the lesson remains that with all nav equipment from sextants to EPIRBS, if you're serious about the safety of yourself and your crew, don't be tempted to skimp on quality - in whatever form that takes.
> 
> ...


I agree--skimping on safety usually results in disaster.  I recently read a book about a young girl that circumnavigated the globe, and during the first leg of her voyage, New York to Bermuda, she was using a plastic sextant--a $149 el cheapo. Because it had been left in a hot location the mirror had distorted and she was nearly 80 miles off course. Fortunately, she eventually found Bermuda after a two weeks of getting pounded by nasty seas. However, it took her several weeks to discover the sextant was defective. She eventually purchased the high-priced spread, learned to use it, and was no longer lost at sea. It was an interesting book, lots of tragedy, and in the end the girl was lucky to survive, let alone make the voyage.

Cheers,

Gary


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## Omatako (Sep 14, 2003)

Hartley18 said:


> I have a Navman Tracker 5430i (internal antenna) chartplotter


Nufsed, it's a Navman, the performance of which you speak is standard with them. My handheld will log on and get a fix in less than a minute unless it's been moved to a different location while being switched off, then it takes a minute or two.


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## Classic30 (Aug 29, 2007)

Omatako said:


> Nufsed, it's a Navman, the performance of which you speak is standard with them. My handheld will log on and get a fix in less than a minute unless it's been moved to a different location while being switched off, then it takes a minute or two.


..and I find this out AFTER I buy the boat!


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## Boasun (Feb 10, 2007)

I for one, Enjoy doing various navigation problems at least two to three different ways. A GPS is for very lazy minds, but it is a good tool to pit your skills against. Have had GPS give me erronious data and used my piloting skills to keep me in waters deeper than the draft of my vessel. But it is a useful tool, but not one that I will depend my vessel survival and the lives of my crew on 100% of the time.


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## sailingdog (Mar 19, 2006)

This was Tania Aebi, who is a well-known sailor and lecturer nowadays.



travlineasy said:


> I agree--skimping on safety usually results in disaster.  I recently read a book about a young girl that circumnavigated the globe, and during the first leg of her voyage, New York to Bermuda, she was using a plastic sextant--a $149 el cheapo. Because it had been left in a hot location the mirror had distorted and she was nearly 80 miles off course. Fortunately, she eventually found Bermuda after a two weeks of getting pounded by nasty seas. However, it took her several weeks to discover the sextant was defective. She eventually purchased the high-priced spread, learned to use it, and was no longer lost at sea. It was an interesting book, lots of tragedy, and in the end the girl was lucky to survive, let alone make the voyage.
> 
> Cheers,
> 
> Gary


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## travlin-easy (Dec 24, 2010)

sailingdog said:


> This was Tania Aebi, who is a well-known sailor and lecturer nowadays.


Thanks, I couldn't remember her name at the time I posted above. The book, which I have read twice, was entitled "Maiden Voyage." It was one of the most fascinating books I've read in years and I can highly recommend it.

The most incredible book about the sea I've ever read was "Miracles On The Water" by Tom Nagorski. It's available through Amazon and it's one of those books that you just cannot put down. You can look inside at Amazon.com: SS City of Benares: Books If this book doesn't bring a tear to your eye nothing will.

Cheers,

Gary


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## T34C (Sep 14, 2006)

Boasun said:


> I for one, Enjoy doing various navigation problems at least two to three different ways. A GPS is for very lazy minds, but it is a good tool to pit your skills against. Have had GPS give me erronious data and used my piloting skills to keep me in waters deeper than the draft of my vessel. But it is a useful tool, but not one that I will depend my vessel survival and the lives of my crew on 100% of the time.


Do your piloting skills turn off when you turn the GPS on????

Let the sky falling begin:

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


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## travlin-easy (Dec 24, 2010)

Those same tests were also conducted when Loran-C was a popular mode of navigation. In reality, most of the testing was done for very brief periods during the middle of the week--not the 45-minute to 1-hour times they initially warned of. In all the years I've been on the water, which I think must have begun when John Paul Jones first joined the Navy, I've only experienced a couple Loran-C outages, both of which were from thundershowers. I've been using GPS for more than a decade and NEVER had a single instance where there was an outage, and the accuracy has ALWAYS been far better than any navigational device I've used since 1957, which was when I joined the U.S. Navy.

While my eyes have always been my primary source of navigation, they're not always accurate--especially at night. Anyone who can look at a blinking light at night and accurately tell you the light's distance is either a damned lucky guesser, or a damned liar. It's nearly impossible to determine distances over water during the day--let alone the night. I would challenge anyone that has never ventured into the entrance of Fairlee Creek in the Chesapeake's upper reaches to find it with a sextant in the middle of the night--it's not gonna' happen! And, you can stare at the lights and charts till you're nearly blind and you'll never find the entrance to Church Creek in the Honga River's upper reaches. There's a reason the U.S. Department of Defense doesn't use a sextant to guide a Polaris or Tomahawk missile to it's target--it uses GPS. And, it uses GPS throughout the world to navigate it's aircraft and ships--NOT sextants.

Yes, it's neat to be able to dead recon, gaze at the stars and sun and get an approximate position, and with luck, get a rough idea where you may or may not be on your charts. But, when it comes to the safety of myself and loved ones aboard a boat, plane or ship, the GPS WILL ALWAYS be MY primary, high-tech, source of navigation. On a cloudy, stormy night, when you don't have a single light, buoy or heavenly body to look at, that sextant is a worthless piece of junk. In contrast, under the same conditions, that GPS will find your position within a few yards and it was able to do this while your thought processes were contemplating whether or not to look at the screen.

Lazy mind? I don't think so. A little smarter maybe by not using an archaic device for navigation when an extremely accurate, high-speed electronic device is available. Whether you're a sailor or power boater, all the senses must come into play and you must be able to utilize every one of them as rapidly as possible. While you're trying to get a fix on the moon you could make better use of your time looking at the electronic depth finder that samples the depth beneath your keel ever 100th of a second. Your eyes would see this information instantly just by shifting your eyes from the horizon to your helm's instrument panel.

I'm not against CN. It's a tool--not a very accurate tool, but it's a tool in an arsenal of navigational tools at your disposal and can be used when ALL ELSE FAILS. The absolute best navigational tool, IMO, is common sense. Unfortunately, as my dear, departed father always said "Common sense isn't very damned common anymore!"

Cheers,

Gary


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## sailingdog (Mar 19, 2006)

A lot of your arguments against celestial navigation are pretty bogus. If you're on the Chesapeake, you should be using coastal pilotage, not celestial navigation. The argument about the accuracy of celestial navigation is pretty bogus to begin with, since it makes little sense to use celestial navigation when you're close to shore. It is generally best used when out in the middle of the ocean, and being off by a mile or five doesn't mean much when you're 1000 miles from land.

For coastal navigation, there's no real need for celestial navigation, since your charts, a good pair of binoculars and a hand-bearing compass should be all you need.

Comparing a cruise missile to a cruising sailboat is also pretty bogus... apples to oranges.

I do have to agree that common sense and the Mark I eyeball are really your best bets for most of your navigation.



travlineasy said:


> Those same tests were also conducted when Loran-C was a popular mode of navigation. In reality, most of the testing was done for very brief periods during the middle of the week--not the 45-minute to 1-hour times they initially warned of. In all the years I've been on the water, which I think must have begun when John Paul Jones first joined the Navy, I've only experienced a couple Loran-C outages, both of which were from thundershowers. I've been using GPS for more than a decade and NEVER had a single instance where there was an outage, and the accuracy has ALWAYS been far better than any navigational device I've used since 1957, which was when I joined the U.S. Navy.
> 
> While my eyes have always been my primary source of navigation, they're not always accurate--especially at night. Anyone who can look at a blinking light at night and accurately tell you the light's distance is either a damned lucky guesser, or a damned liar. It's nearly impossible to determine distances over water during the day--let alone the night. I would challenge anyone that has never ventured into the entrance of Fairlee Creek in the Chesapeake's upper reaches to find it with a sextant in the middle of the night--it's not gonna' happen! And, you can stare at the lights and charts till you're nearly blind and you'll never find the entrance to Church Creek in the Honga River's upper reaches. There's a reason the U.S. Department of Defense doesn't use a sextant to guide a Polaris or Tomahawk missile to it's target--it uses GPS. And, it uses GPS throughout the world to navigate it's aircraft and ships--NOT sextants.
> 
> ...


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## Omatako (Sep 14, 2003)

travlineasy said:


> I've been using GPS for more than a decade and NEVER had a single instance where there was an outage . . . . . . But, when it comes to the safety of myself and loved ones aboard a boat, plane or ship, the GPS WILL ALWAYS be MY primary, high-tech, source of navigation.
> 
> Lazy mind? I don't think so. A little smarter maybe by not using an archaic device for navigation when an extremely accurate, high-speed electronic device is available.


I agree with all of the above.

Most folks today use calculators rather than mental/written arithmetic, also send e-mails rather than write letters, also visit forums rather than go to meetings, also take digital pictures rather than using film cameras, also travel in cars rather than walking, also use couriers rather than delivering stuff themselves, the list is actually endless. But use GPS? Nooooo, that's the sign of a lazy mind.

I guess if the Amish went sailing they'd probably use a sextant but there's little need for the rest of us to do so.


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## AdamLein (Nov 6, 2007)

Omatako said:


> Most folks today use calculators rather than mental/written arithmetic, also send e-mails rather than write letters, also visit forums rather than go to meetings, also take digital pictures rather than using film cameras, also travel in cars rather than walking, also use couriers rather than delivering stuff themselves


I find most of these behaviors deplorable 

And while I may be guilty of all of them, I think that being able to resort to their low-tech counterparts is in all cases a virtue.


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## rockDAWG (Sep 6, 2006)




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## AdamLein (Nov 6, 2007)

Never! Not until the other side admits they were wrong all along and begs us to show them the light!


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## travlin-easy (Dec 24, 2010)

Think I'll mix up another Green Coconut Margaretta! 

Gary


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## T34C (Sep 14, 2006)

rockDAWG said:


>


Now what fun would that be?


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## dougshipl (Jan 22, 2007)

Every blue water cruiser should have some understaning of it as it's really not that difficult. I learned the basics at age 12. If you can add and subtract you can do celestial navigation. Its just a lengthy process in our GPS world. Sun is typically the easiest of the shots but you can use the moon, 5 of the brightest plants or 57 stars. Invest in a cheap Davis sextant a reliable digital watch that you can adjust to England time, a 2011 Nautical Almanac at West Marine and pick up the DVD Celestial Navigation for Beginners by Magic Lamp Productions. It was done a while back by a now retired instructor at the US Naval Academy. It's boring to watch but really shows how idiot proof the process is. You can find it 
on line or Amazon. That's all you need - all for under$250 bucks and you'll get within 2 miles of your location. Like I said, it's good to know but sadly I haven't touched any one of my 3 Sextants in 10 yrs. Our wizbang E80s with radar, Google Earth and weather front overlays have spoiled us.


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## AdamLein (Nov 6, 2007)

While everything else you said is true, it's clear from this thread that not everybody agrees with this bit:


dougshipl said:


> Every blue water cruiser *should*


(emphasis mine)


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## Boasun (Feb 10, 2007)

Actually when you are far far offshore, You can do all the celestial all you want. But in reality you only need to take a sighting at dawn, noon and Sunset (Sun only) and do a running fix. When you come into sight of land you start with the Coastal piloting. Then you add in the stars, planets and the moon, as your skills improve.
Simple isn't it. Of course coastal piloting can be a tad more involved in taking bearings, radar ranges and what not. Pitting yourself to the GPS and seeing if you are more correct then the GPS... And there are times when you will be. 

Note: Sunrise & Sunset will give you Longitude, while the Noon sight will give you latitude.
Note2: While sailing as a third officer on the big ships, I was required to have at least three sun lines and work out Local Apparent Noon. This was on the 0800~1200 watch.


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## sailingdog (Mar 19, 2006)

This is what I keep saying, but people keep insisting that you need to use CN when in sight of shore.



Boasun said:


> *Actually when you are far far offshore, You can do all the celestial all you want. But in reality you only need to take a sighting at dawn, noon and Sunset (Sun only) and do a running fix. When you come into sight of land you start with the Coastal piloting.* Then you add in the stars, planets and the moon, as your skills improve.
> Simple isn't it. Of course coastal piloting can be a tad more involved in taking bearings, radar ranges and what not. Pitting yourself to the GPS and seeing if you are more correct then the GPS... And there are times when you will be.
> 
> Note: Sunrise & Sunset will give you Logitude, while the Noon sight will give you latitude.
> Note2: While sailing as a third officer on the big ships, I was required to have at least three sun lines and work out Local Apparent Noon. This was on the 0800~1200 watch.


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## Sublime (Sep 11, 2010)

I want to get a sextant and learn to use it. It's a good exercise for the brain, if anything. 
Not with sailing so far, but I've been put in situations where important electrical equipment fails...either a fluke, or getting broken, etc. It's never as easy as the batteries dieing. It's always something you haven't planned on. I always have a mechanical backup on very important things or a way to go without.

I can count on the sun and stars. I'd be nervous to count on electrical equipment or satellites. I just can't do it. I've had those types of things fail too often. I can use things like GPS. It's nice so I don't _have_ to use charting and such. I'm not going to let that be my only means of navigation because I'd like to get back home.

Redundancy will bring you home.


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## svs3 (Jun 23, 2006)

CN and GPS are great and all. But they're just tools. Ultimately, it is your knowledge, skill, and experience that determine whether a given voyage is completed safely ... or not.


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## tdw (Oct 2, 2006)

Hartley18 said:


> I would not agree with that assessment for one second.
> 
> eg. I have a Navman Tracker 5430i (internal antenna) chartplotter that, according to many here, I'm supposed to be able to rely on whilst navigating my way around. It has a few issues:
> 1. The manual states it could take a minute or two on a good day, but I've only managed to get satellite lock about 1-in-4 times I've turned the thing on (in the cockpit in clear view of the sky).
> ...


Cameron,
This is a bit late in reply I know but I've only just seen this thread.
We have a 5430 but because I intended installing it at the chart table with a cockpit repeater it does not live outside. Of course we are steel so ours is external aerial. 
When I turn the thing on it takes no longer than my Garmin hand held units to power up and lock onto satellites. Agreed the screen is too small. I never use it. Get lat/long, plot onto paper, does me. 
To be honest I very rarely use the Navman as the Garmin uses less juice and works just as well. 
Navman , btw, have the most apalling record for quality. Surprising for a Kiwi business, the stuff is basically junk but it was low cost. Navman is also no more in the marine business, they sold out to someone and is now rebranded as Northstar. Presumably it is just as crappy.
Maybe for your racing you need more than this but if I were you I'd get myself a Garmin handheld with a mounting bracket and install it just inside the companionway where you can see it from the helm. Ours is not even the waterproof unit and despite some serious drenching it still plods along. For peace of mind though I wish we had spent the extra and bought the waterproof version. 
Cheers
Andrew


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## Classic30 (Aug 29, 2007)

tdw said:


> Cameron,
> This is a bit late in reply I know but I've only just seen this thread.
> We have a 5430 but because I intended installing it at the chart table with a cockpit repeater it does not live outside. Of course we are steel so ours is external aerial.
> When I turn the thing on it takes no longer than my Garmin hand held units to power up and lock onto satellites. Agreed the screen is too small. I never use it. Get lat/long, plot onto paper, does me.
> ...


Hi A, funny you should suggest that! One of my crew for Geelong Week brought along his Garmin GPSMap76 handheld to give us a rough idea of where (over the horizon) the next turning mark was. I thought it was brilliant!! 

It was waterproof enough that it could sit on the seat beside me, I could actually read the screen (just), and it told me everything I needed to know (speed and course mainly). It even saved our bacon on the way back to Melbourne in the dark, by giving me enough of an idea of our distance off the dark shoreline with the lights of the city behind, to pick out the red flashing beacon we needed that wasn't the tail-light of a car and ignore the other red flashing beacon that marked Altona wetlands.

I'll be getting one..


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## travlin-easy (Dec 24, 2010)

The last time I used a sextant was last year on a windy day while sailing in my Catalina 27. The best accuracy I could get was +/- 4.5 miles, which would be find if you were 30 or more miles offshore. If you were looking for the entrance to most of the inlets along the east coast of the United States and hoping to duck inside to avoid a storm, you would be in a heap of trouble. Most of the inlets south of Ocean City, Maryland are tough to find without electronics. There are no land marks, no buildings, nothing on the horizon but a sea of sand dunes and grasses. If you're lucky enough to find a buoy or day marker, especially on a nasty weather day, you then have to determine where that buoy is located on your chart so you can determine your approximate position. Those coastal piloting skills are just fine if you have something to look at, but there are lots of places between Ocean City, MD and Key West, FL where there are miles and miles of nothing but miles and miles of sand dunes, low trees and grass. Funny how they all tend to look the same. Three inlets that immediately come to mind are Great Machapongo Inlett, Shipshoal Inlet and New Inlet, all of which are situated between Wachapreague and Cape Charles, VA. They're great locations that will provide excellent shelter from some nasty storms, but without electronics I seriously doubt that you could find them. I've spent lots of time going through all three inlets and I wouldn't attempt to find any of them without electronics.

I sincerely hope that everyone who wishes learns to use a sextant with some degree of accuracy has better luck than I did. Oh, one more thing. Sextants CAN, and often DO, fail! Keep in mind it is a mechanical device that has a few variables that must be precise in order to function. The alignment of the mirror and optics is of paramount importance and must be carefully inspected before use. This is especially true with the plastic models.

Gary


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## sailingdog (Mar 19, 2006)

This is why, traditionally, you would aim to make landfall clearly to one side of the port, so that you can use your coastal pilotage skills to get to the harbor entrance safely.

BTW, trying to make inlets in bad weather is generally a bad idea IMHO. You're often far safer staying in deep water than you are trying to risk entering many harbors. If you don't have the time to make the landfall safely, stay in deep water.



travlineasy said:


> The last time I used a sextant was last year on a windy day while sailing in my Catalina 27. The best accuracy I could get was +/- 4.5 miles, which would be find if you were 30 or more miles offshore. If you were looking for the entrance to most of the inlets along the east coast of the United States and hoping to duck inside to avoid a storm, you would be in a heap of trouble. Most of the inlets south of Ocean City, Maryland are tough to find without electronics. There are no land marks, no buildings, nothing on the horizon but a sea of sand dunes and grasses. If you're lucky enough to find a buoy or day marker, especially on a nasty weather day, you then have to determine where that buoy is located on your chart so you can determine your approximate position. Those coastal piloting skills are just fine if you have something to look at, but there are lots of places between Ocean City, MD and Key West, FL where there are miles and miles of nothing but miles and miles of sand dunes, low trees and grass. Funny how they all tend to look the same. Three inlets that immediately come to mind are Great Machapongo Inlett, Shipshoal Inlet and New Inlet, all of which are situated between Wachapreague and Cape Charles, VA. They're great locations that will provide excellent shelter from some nasty storms, but without electronics I seriously doubt that you could find them. I've spent lots of time going through all three inlets and I wouldn't attempt to find any of them without electronics.
> 
> I sincerely hope that everyone who wishes learns to use a sextant with some degree of accuracy has better luck than I did. Oh, one more thing. Sextants CAN, and often DO, fail! Keep in mind it is a mechanical device that has a few variables that must be precise in order to function. The alignment of the mirror and optics is of paramount importance and must be carefully inspected before use. This is especially true with the plastic models.
> 
> Gary


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## Omatako (Sep 14, 2003)

sailingdog said:


> BTW, trying to make inlets in bad weather is generally a bad idea IMHO. You're often far safer staying in deep water than you are trying to risk entering many harbors. If you don't have the time to make the landfall safely, stay in deep water.


There is a strong logic in what you say but when you have been getting beaten up by bad weather at sea for a week and you're standing off a safe anchorage in thumping weather, the desire to run for cover can become irrationally strong . . .


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## AdamLein (Nov 6, 2007)

Omatako said:


> when you have been getting beaten up by bad weather at sea for a week and you're standing off a safe anchorage in thumping weather, the desire to run for cover can become irrationally strong . . .


Worst possible mindset for trying to cross an inlet in bad weather, regardless of how many newfangles gizmos you've got on board.


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## svs3 (Jun 23, 2006)

> when you have been getting beaten up by bad weather at sea for a week and you're standing off a safe anchorage in thumping weather, the desire to run for cover can become irrationally strong . . .


This is known in mountaineering circles as "summit fever" the desire to get the summit (or port) despite the overwhelming objective dangers. Failure to recognize it and turn back (or turning back too late) has been at the root of many, otherwise avoidable, mountaineering (and sailing) tragedies. Resisting it is considered to be one of the signs of a wise and experienced mountaineer (and sailor), IMHO.

The same applies to sailing and sailors.


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## sailingdog (Mar 19, 2006)

And if you become irrational and give into it, there's a pretty good chance you end up a statistic like they did on Rule 62.



Omatako said:


> There is a strong logic in what you say but when you have been getting beaten up by bad weather at sea for a week and you're standing off a safe anchorage in thumping weather, the desire to run for cover can become irrationally strong . . .


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## Omatako (Sep 14, 2003)

I never said it was right or OK, I just said that it exists. 

Bottom line I guess is that many do give in to it and that is why we get this constant stream of clips on this board that we appear to enjoy so much showing boats crashing into anchorages and harbours.


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## travlin-easy (Dec 24, 2010)

I think the irrational aspect of this would be to NOT utilize the accuracy of a GPS, try to make landfall somewhere north of south of the inlet within the accuracy of the CN system, than spend a couple hours battling wind and waves while trying to find the inlet.

Lets flip a coin. Should I make a WAG (wild assed guess) as to what the weather is really going to do, stay offshore and get the hell beat out of me, the crew and the boat? Or, should I use the GPS and go directly to the inlet before the weather worsens? Hmmmm! Think I'll go with the GPS and dodge the worsening weather conditions.

Good Luck,

Gary


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## Ferretchaser (Jan 14, 2011)

Just my two cents and yes I have learned CN is that a sextant is not an essential bit of kit to have on board any more. Even in the unlikely event, that all GPS system on board fail, the boat is not going to sink because of it and you are not going to die just because you are now left with DR and a compass, pilot charts and a log. Chances are that you are going to get to shore, maybe not in the exact place you wanted, but you are going to run out of water at some point. 
I am not trying to discourage anyone from learning or using a sextant. I think that it is good to keep these traditional skills alive and still like to lite a camp fire with a bit of tinder and a few sparks as well but on a day to day basis I find using a lighter just more convenient. 
Then there is the argument I sometime hear, that in some places a GPS fix is out by up to 2 miles because the time the area has been charted, it was done by CN. That does not mean, that I am going to be more accurate with a sextant in those areas by adding my mistakes to the ones the folks made when they drew the charts of those places. So I rather be a mile or two out using GPS then 5 or ten using a sextant. 

Just my two cents worth.

Michael


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## chrisncate (Jan 29, 2010)

travlineasy said:


> *I think the irrational aspect of this would be to NOT utilize the accuracy of a GPS*, try to make landfall somewhere north of south of the inlet within the accuracy of the CN system, than spend a couple hours battling wind and waves while trying to find the inlet.
> 
> Lets flip a coin. Should I make a WAG (wild assed guess) as to what the weather is really going to do, stay offshore and get the hell beat out of me, the crew and the boat? Or, should I use the GPS and go directly to the inlet before the weather worsens? Hmmmm! Think I'll go with the GPS and dodge the worsening weather conditions.
> 
> ...


No thanks:



> The Global Positioning System faces the possibility of failures and blackouts, a federal watchdog agency has warned the U.S. Congress. Mismanagement by and underinvestment by the U.S. Air Force places the GPS at risk of failure in 2010 and beyond. The problem: Delays in launching replacement satellites, among other things.
> 
> According to the Government Accountability Office report, "In recent years, the Air Force has struggled to successfully build GPS satellites within cost and schedule goals" as part of a $2 billion modernization program.
> 
> "If the Air Force does not meet its schedule goals for development of GPS IIIA satellites, there will be an increased likelihood that in 2010, as old satellites begin to fail, the overall GPS constellation will fall below the number of satellites required to provide the level of GPS service that the U.S. government commits to."


GPS System Could Begin to Fail Within a Year - PCWorld Business Center


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## Ferretchaser (Jan 14, 2011)

Yes there is going to be the odd black spot here and there, but they are going to get it sorted out because the military depends on the system. even with the odd black out, GPS is still going to be more dependable then CN on a cloudy or clear day for that matter.


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## chrisncate (Jan 29, 2010)

Ferretchaser said:


> Yes there is going to be the odd black spot here and there, but they are going to get it sorted out because the military depends on the system. even with the odd black out, GPS is still going to be more dependable then CN on a cloudy or clear day for that matter.


I'd stick with having no time constraints or deadlines, and heaving to well offshore while waiting for the right conditions, over relying on _any_ electronic devices.

I'm old fashioned though, and my boat heaves to very well...


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## jackdale (Dec 1, 2008)

chrisncate said:


> I'd stick with having no time constraints or deadlines, and heaving to well offshore while waiting for the right conditions, over relying on _any_ electronic devices.
> 
> I'm old fashioned though, and my boat heaves to very well...


+1

I would never enter an unfamiliar harbour at night or in restricted visibility.


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## svs3 (Jun 23, 2006)

> I would never enter an unfamiliar harbour at night or in restricted visibility.


+1

Words to live by, literally.


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## HDChopper (Oct 17, 2010)

Probbly the best lesson I have taken from all the fine sailers here at SN is thissin " RULE 62 " lesson after all once looked at in the light it was just plain common sence ...Yes there is everything in the world going on to persuade you to a different answer but fall back on rule #1 = keep your cool and do the right thing ! Thank you RULE 62 & crew & Sailnet!

That said my brain tells me you crawl before you walk,,,I just bought a damn good watch for CN in future now looking for what everyone thinks is the best "accurate" with in reason of the watchs abilitys 2 sec per month..

I was thinking getting a "used" Mark 25 Davis Sextant and getting a new mirror for it ...make since ??? if not hammer away plz...


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## Ferretchaser (Jan 14, 2011)

chrisncate said:


> I'd stick with having no time constraints or deadlines, and heaving to well offshore while waiting for the right conditions, over relying on _any_ electronic devices.
> 
> I'm old fashioned though, and my boat heaves to very well...


I did not imply that I would enter a unknown port at night. I rather wait it out till the conditions are right. The most dangerous thing to have on board is a calendar.


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## sailingdog (Mar 19, 2006)

I'd point out that racing to beat the weather gets a lot of sailors killed each year. Also, if you've made the decision to get into a harbor, often you'll try to do so, even if the conditions worsen and doing so becomes riskier than staying out, since most people tend to get stuck on a plan once they've made a decision.

I'd rather take the beating and live, than try for the harbor and die trying. Most boats aren't fast enough to make a damn difference when it comes to beating a storm, unless you have a fairlylong lead time.



travlineasy said:


> I think the irrational aspect of this would be to NOT utilize the accuracy of a GPS, try to make landfall somewhere north of south of the inlet within the accuracy of the CN system, than spend a couple hours battling wind and waves while trying to find the inlet.
> 
> Lets flip a coin. Should I make a WAG (wild assed guess) as to what the weather is really going to do, stay offshore and get the hell beat out of me, the crew and the boat? Or, should I use the GPS and go directly to the inlet before the weather worsens? Hmmmm! Think I'll go with the GPS and dodge the worsening weather conditions.
> 
> ...


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## Boasun (Feb 10, 2007)

Quote:
I would never enter an unfamiliar harbour at night or in restricted visibility. Quote: 

When I was working commercially, this is what I've had to do many times.
It got to the point that every time I'm entering a new port it is always dark thirty or thick fog. Was sucessful every time. Mainly due to the fact that I read Coast Pilot for that port and studied the charts carefully. Time contrains and company expectations were the main reasons. But I've been sailing Commercially since Feb. '79 after retiring from the Navy Jan. '79 after 21 years as a Boatswain's Mate. So you could say that I've had a tad amount of sea time.

NO I don't recommend a boat skipper who goes sailing as a hobby to try this. The reason is the high pucker power down south on your body.....


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## sailingdog (Mar 19, 2006)

Large commercial ships tend to have a bit more power and deal with heavier seas a good deal better than a small recreational sailboat. They also are generally better crewed.



Boasun said:


> Quote:
> I would never enter an unfamiliar harbour at night or in restricted visibility. Quote:
> 
> When I was working commercially, this is what I've had to do many times.
> ...


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## Classic30 (Aug 29, 2007)

sailingdog said:


> Large commercial ships tend to have a bit more power and deal with heavier seas a good deal better than a small recreational sailboat. They also are *generally better crewed*.


*HAH!.. *You MUST be joking!! A bunch of half-drunk Fillipinos are a "better crew"???   Obviously you haven't been on any commercial shipping lately, SD. 

The biggest thing commercial ships have going for them are a little group called SEA PILOTS who make it their business to ensure commercial ships get into their particular port relatively unscathed - and lose their job if they don't.

Give credit where it's due, please..


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## JonEisberg (Dec 3, 2010)

jackdale said:


> +1
> 
> I would never enter an unfamiliar harbour at night or in restricted visibility.


Probably just me, but I prefer "Never say never&#8230;" Or, in other words, "It depends&#8230; " (grin)

No question, it's an excellent rule of thumb&#8230; but, I've always thought it make more sense to assess each situation individually, which in the long run results in superior seamanship, IMHO&#8230;

Given reasonable or favorable conditions, many harbors can be safely entered after dark&#8230; frankly, anyone incapable of entering Port Everglades, or Beaufort, NC, for example, after dark likely has no business being on the water at night to begin with&#8230;

Same thing with poor visibility, sometimes you really have no good options&#8230; Say you've made a passage to Nova Scotia for the first time, and are making landfall at Lunenberg&#8230; Every harbor on that coast is gonna be unfamiliar to you. If it's in July, there's a good chance you haven't had more than 100 meters of visibility for the last 100 miles&#8230; Are you really heave-to off Lunenberg for a week, perhaps more, until the fog dissipates?

Again, it's a good rule of thumb, no question&#8230; But, I think there are many instances in which it can be "broken" safely, given sufficient experience and situational awareness&#8230;


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## travlin-easy (Dec 24, 2010)

If I never entered an unfamiliar harbor or inlet at night I would have spent most of my life at sea waiting around for better weather and daylight.  My first trip through Oregon and Hatteras inlets were damned well frightening--both are nothing more than slots in the surf. I've been through both several times since, and while it's always a bit exhilarating, there has only been a few times that I opted to remain a few miles offshore until the tide slacked. The wind never seems to slack at the Outer Banks, though. 

Good Luck,

Gary


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## travler37 (Mar 30, 2007)

Ferretchaser said:


> Yes there is going to be the odd black spot here and there, but they are going to get it sorted out because the military depends on the system. even with the odd black out, GPS is still going to be more dependable then CN on a cloudy or clear day for that matter.


 The "Military" depends on the system and also jammes the system.Worse they send a false signal that they have compensated for in there systems but will put you 20+ miles off.I hope you never go through the frustration of having your celest.sights being consistently off and not knowing why.Take a sextant to a war zone and compare your shots to your gps and see....grins.
That said you will never enter a harbor with a sextant.Just find the entrance if your good.As for entering a strange harbor at night with a gps,much less with somebody else's waypoints.......is your life insurance paid up?
My Thoughts
Mark


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## travler37 (Mar 30, 2007)

If you do not think the mimitary messes with your signal,

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

What are our chart-plotter friends going to do?:laugher 
mark


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## travlin-easy (Dec 24, 2010)

These tests have been going on since GPS became available. While they can last up to 45 minutes, most of the time the test lasts less than 5 minutes, and very few people seem to have noticed. Aircraft using GPS have lots of backup systems, including transponders, which are linked to ground radar control systems. To my knowledge the tests are never conducted at night, and most occur in the middle of the day in the middle of the week, times when most boaters are too busy watching the horizon.

Rarely, even in war zones, is there a complete outage of GPS. Granted the accuracy isn't pin-point, but it ain't 20-miles off! Now, I don't know about most folks on this form, but I'm going to avoid war zones and other locations where I would put myself or others in harms way. If you want to sail the Somalia Coast using your sextant, knock yourself out. I'll stick to the sunny shores of the U.S. and countries where sailing is fun--not a life-threatening challenge of everyday life.

Good Luck,

Gary


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## AdamLein (Nov 6, 2007)

travler37 said:


> Take a sextant to a war zone and compare your shots to your gps and see....grins.


Only 20 miles off? You might not see a difference...


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## cb32863 (Oct 5, 2009)

And another example of the increased reliance on technology being 100% accurate and not using the ol' common sense noggin...

LINK


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## sailingdog (Mar 19, 2006)

cb32863 said:


> And another example of the increased reliance on technology being 100% accurate and not using the ol' common sense noggin...
> 
> LINK


You can't fix STUPID.


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## travlin-easy (Dec 24, 2010)

Lets see now--should we blame the GPS? Or, should we blame the idiot that was so stupid that she drove into Death Valley during the height of summer (120 degrees f) with a 6-year-old kid, and wasn't smart enough to carry food, water, etc.., which is posted on signs everywhere you drive in this area? 

Blame the GPS, of course. Now you can bring a class action suit against the manufacturer, and sue them for millions. Whoops, better also sue the USGS for not updating the maps and telling everyone that road was closed. (She probably didn't read that sign either.) What the Hell was on her mind. Driving alone with a a 6-year-old kid, in the middle of the nation's largest,hottest desert just isn't real smart. 

My long deceased father had some pretty neat sayings that I would like to pass along. "The average person is well below average." And, "Common sense isn't very damned common these days." 

Ironically, the idiot that wrote that story had to search long and hard to come up with this one. There are probably 50-million people using GPS systems every day without encountering a problem. He managed to find one and tried to make a front-page story out of it. I guess he was looking for some sort of blood and guts sensationalism type of story that was really unique, instead of the regular, daily blood and guts stories like car wrecks, homicides, wars, rapes, floods, earthquakes, volcano eruptions, plane crashes, etc... 

Cheers,

Gary


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## chrisncate (Jan 29, 2010)

I say (and will myself) use a combination of GPS and traditional navigation techniques (celestial) once we get underway next fall.

I think as long as you have the know how to back up your high tech with "low" tech in a pinch, and verify both against each other, you're all good.

I _really_ look forward to using celestial navigation though


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## AdamLein (Nov 6, 2007)

The case that the "idiot author" of that article is trying to make is that unskilled people who encounter technology tend to believe it makes them more skilled than they really are (i.e. more than native skill + skill through technology). This happens because the technology gives them _access_ to activities they once thought (correctly) were out of their reach.

In any case I don't see the "idiot author" anywhere actually blaming the GPS, or making any sort of annoying calls for legislative action to protect us from technology or ourselves, though I only glanced through the article. It seems like more of a "I see this disturbing trend in my society, just thought I'd letcha all know," article.


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## travlin-easy (Dec 24, 2010)

First and foremost, look at the article's title "Death By GPS in Desert," thus leading the reader to immediately assume the GPS was the cause of death--not stupidity. Next, some of the sub-titles add to the headline "Not All GPS Units Reliable," a statement that is not really as accurate as the GPS units themselves. Most GPS units are extremely reliable, but like computers, they only do what you tell them to do.

GPS units are no more complex than a cellular telephone that has all the bells and whistles. The problem is that most people don't take the time to read the instruction manuals that come with them. Of course, some people cannot read at all, or they're just too damned lazy to read the manual, then wonder why something doesn't work the way they want it to work. Hmmmmm! Kinda like trying to use a sextant without first reading the book and learning how to use it. Imagine that! 

Gary


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## AdamLein (Nov 6, 2007)

Doesn't matter if you know how to use the GPS and if you know its limitations. If you have lived a life where you put your trust in technology without thinking twice, then you'll drive off into the desert, trusting your GPS to make it a safe thing for you to do. In fact I would bet that even if the manual said "CAUTION: DO NOT DRIVE OFF INTO THE DESERT RELYING SOLELY ON YOUR GPS UNLESS YOU HAVE WILDERNESS SURVIVAL EXPERIENCE", and even if the woman had read the instructions carefully, she _still_ would have made the decisions she did.

It's the black-box nature of GPS and all sorts of technology. If I can press a button and get a result, _then I am unstoppable_. I don't see the type of person who puts all their faith in a magical black box to be the type to rely on a sextant for navigation, so statistically it will come up less often. A sextant makes a terrible black box since you must be intimately familiar with its workings in order to use it. A person who is not accustomed to dependence on black-box type devices is more likely to carefully plan their activities, consider contingencies, etc.

So while "Death By GPS" may be a bit sensationalist, the author is really getting at a behavioral trend in humans that is permitted by black box technology. Is it a reason for hardened cruisers to avoid GPS? Probably not. Is it a reason for society in general to think twice about grabbing every gadget they can? I would probably have to agree.


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## sailingdog (Mar 19, 2006)

Unfortunately, I'd have to agree that the woman in the story probably wouldn't have gone to Death Valley had she not had the GPS. So, in that sense, the GPS did cause her death. *However, the real cause of her daughter's death was the mother's complete stupidity about a very hostile and dangerous environment.*

The same thing has happened to sailors with GPS...and those that relied on its "accuracy and infallibility" and gotten into trouble because they didn't understand the basic environment that they were in-the ocean. Rule 62 is a good example of this.


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## jackdale (Dec 1, 2008)

Some time ago I posted a story about an elderly couple who drove down an unplowed road in the winter and got stuck. They survived.

There is also a story about a yacht using a GPS that hit a charted reef in Australia.

SD - you could make a fortune selling Mark I eyeballs.


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## sailingdog (Mar 19, 2006)

Unfortunately, using Mark I eyeballs requires a modicum of common sense and intelligence to work... and that's become pretty rare.



jackdale said:


> Some time ago I posted a story about an elderly couple who drove down an unplowed road in the winter and got stuck. They survived.
> 
> There is also a story about a yacht using a GPS that hit a charted reef in Australia.
> 
> SD - you could make a fortune selling Mark I eyeballs.


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## cb32863 (Oct 5, 2009)

sailingdog said:


> Unfortunately, using Mark I eyeballs requires a modicum of common sense and intelligence to work... and that's become pretty rare.


Which was my point in posting the link to the story...


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## sailingdog (Mar 19, 2006)

cb32863 said:


> Which was my point in posting the link to the story...


Yup... it was


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## travlin-easy (Dec 24, 2010)

Geez, there you go with that common sense thingy again--ain't it amazin'! 

Gary


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## svHyLyte (Nov 13, 2008)

Common sense seems to be an all to uncommon. Not long ago we heard someone hailing the CG. We switched up to 22A to ease-drop on the ensuing conversation which involved a concerned boater that wanted to let the CG know that, according to his GPS, they had put the outer marker at the mouth of the Manatee River in the wrong place! The CG watch stander patiently thanked him for the tip.

FWIW...


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## Boasun (Feb 10, 2007)

Actually; Mark I eyeballs come as a set with a Working Brain.
I believe that the key word there is "Working".


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## HDChopper (Oct 17, 2010)

Heehehehehehe so eloquently put Boasun ....


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## jack2 (Sep 26, 2009)

*Sextant Choice*

I am not sure if this is the right place to ask, but do any of you have experience with the Freiberger Yacht Sextant or the ASTRA III B sextant. I realize the the Freiberger is smaller and somewhat more expensive but it is not from China, (products from which I prefer not to buy). Any thought about the quality and functionality of these. Thanks


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## sailingdog (Mar 19, 2006)

jack2 said:


> I am not sure if this is the right place to ask, but do any of you have experience with the Freiberger Yacht Sextant or the ASTRA III B sextant. I realize the the Freiberger is smaller and somewhat more expensive but it is not from China, (products from which I prefer not to buy). Any thought about the quality and functionality of these. Thanks


The Freiberger is smaller, better built, nicer materials, but IIRC, not made anymore. It is also usually more expensive than a new ASTRA III B sextant, which is a current model and has parts easily available.

I'd imagine the accuracy and functionality is mostly dependent on the design, and an older Freiberger may not be as accurate, especially if it is a vernier rather than a micrometer drum design, and may not be as functional.


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## riversandbar (Jan 13, 2011)

Sorry if this has already been asked... but didn't read the full 15 pages of posts... although I should.. LOL

Was thinking about picking up a platic training sextant.... what are your thoughts on it for training and possible usage in the lifeboat afterwards. Is it worth the money?


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## Boasun (Feb 10, 2007)

A plastic sextant is better than nada. So go for it.


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## sailingdog (Mar 19, 2006)

riversandbar said:


> Sorry if this has already been asked... but didn't read the full 15 pages of posts... although I should.. LOL
> 
> Was thinking about picking up a platic training sextant.... what are your thoughts on it for training and possible usage in the lifeboat afterwards. Is it worth the money?


Provided you check the sextant very carefully for alignment and such to minimize errors related to those problems and make sure the sextant hasn't warped. Don't leave plastic sextants out in the sun, as Tania Aebi can tell you.


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