Navigation poll

[Lodesman]

I just realized "call the coast guard" isn't such a bad response - if you call the local coast guard radio or vessel traffic services, they can usually DF you, which a good way to get a line of bearing if not a fix, when visual and celestial are not options.

Kevin

[hellosailor]

Rick-
We all know guys don't ask for directions, because we know the guys giving them have no f*ing idea but they're gonna bluff and give us wrong ones anyway.

Go for a $500 new Astra or Ares and it will be good enough. For a bit more you can get a top model C&P on the used market if you are patient, the problem being that you don't know how good it is or if it really is in straight, without checking it out. The better sextants really do have some subtle niceties and can be more accurate--but on a moving boat at sea, I don't think the last half mile in a celestial fix is what you're going to be worried about.

[Amgine]

Kidding! just kidding!

An interesting comment on modern navigation from someone who spent the first ten years of their sailing career bumming around the south pacific with nothing but celestial was "I use GPS. My back up is GPS. And my back up to back up is a GPS. And I keep an unused GPS in a steel cage in the bilge with extra batteries, in case of lightning strike."

Not that he's confident in the US satellite system or anything.

I used to have a calculator I'd programmed for sight reductions. I may have to do that again sometime...

[Strygaldwir]

Is celestial navigation really that reliable?? What happens if the book with the sight tables get lost, wet, burns up, ink runs, ink fades, boll wevils eat the paper, paper moths eat the paper, mildew eats the paper, rot eats the paper, I get hungry, I eat the paper??

What about the sextant!! What happens if the silver on the mirror wears off? I drop it? it rust? it melts? there are too many clouds to see the sun, there is too much rain to see the sun? too many clouds to see the stars? There's a war and the government decides to turn off the sun so the machines can get recharged?

I guess I'll go back to my corner now.

[AutumnBorne1]

wow...
That's a lot of "what-if"s...
The truth is... with even the crudest of instruments, you can get your latitude (assuming you sail in the northern Hemisphere) from observing the altitude of Polaris. It will roughly match your present latitude.

If the weevils, and Neptune are good to you, and leave just a few tables, and a good watch, a noonsite will give you your longitude.

At least you'd be doing something to get you going in the correct direction.

You can measure angles with other things besides a Sextant, but I wouldn't count on hitting Bermuda with a CD, pencil and string plumb-bob.
Take care of that sextant ! don't drop it, or keep it in the bilge.


Good Luck.

[hellosailor]

Amgine-
Forget about the calculator, get John Manson's sightings/piloting/navigation program for the Palm, and any old Palm used for $30 should run it. Complete sight reduction and many other tools in the new versions.

[markw9692]

I'm a new member,and don'tknow how to ask ?s,where to go to do it & what buttons to push,so here I am trying.I'm Mark,a new boat owner,Galaxy32,1963,that needs lots of help. I own a small hardwood floor business,therefor I'm a finisher by trade and generally handy.and not afraid of work.There is a used boat part consignment ctre. in Rhode Island near me.I need a GPS since I lack needed Nav. skills,advice welcomed.I need advice on emeron vs. interlux hull paint,and advice on filler(epoxy with Micro-pillows?).Advice on what grits of sandpaper to final finish hull and bottom on re-coating.It looks like excessive coats of bottom paint have been applied without proper prep prior to re-coating(lots of removal needed). An ablative bottom paint was used 7yrs prior to my purchase(Iknow not ablative)and thats seven years annualy.I need advice on bottom paint brands,pettit?I need advice on how to locate a person at atlantic heights municipal marina in atlantic heights NJ,where boat now resides.I ccoul use help with boat movers,if someone knows of reliable overland movers in an affordable realm. I love old things.This boat is anearly 1963 Bill Tripp design,32'Galaxy whose hull lines and 1khr yanmar 3cyl 27 hrs. diesel I fell in love with.Any help would be appreciated,truly. I'm swamped in hardwood floors(good thing....I have aboat to support),am burning the candle at both ends and need to move this boat by May,if possible. I'd like to go to the boat for 1-2weeks prior to May and prep both bottom and hull and re-coat. thanks Mark,aurthor@cox.net.

[Amgine]

Originally Posted by hellosailor

Amgine-
Forget about the calculator, get John Manson's sightings/piloting/navigation program for the Palm, and any old Palm used for $30 should run it. Complete sight reduction and many other tools in the new versions.

Yep! but in order to program the calculator (or whatever) I'll have to learn more about how to calculate the celestial, which is what I'm really trying to do - force myself to understand the problem very completely. For the same reason I once designed/built a sail, so I would understand all the steps (which is also why I'll never do that again...)

[SkiprJohn]

Thanks for the opportunity to respond. I know celestial navigation and have a really great sextant. I don't need to call the Coast Guard and don't want the attention. I don't want to admit I'm stupid. If it is close to shore and the last time I got a GPS fix then DR is good. If offshore and awhile since last fix then celestial comes into play. I've got N. A. and H. O. 249 plus all the forms to do the calculations so I'm good to go plus paper charts. Not a problem. How about you?

I also have two plastic Davis Mark 15s extra. I'm willing to let them go at a reasoanable price but it has to be an easy deal. You tell me where you live. I tell you how much I want for the sextants + shipping and we do it via paypal. The sextants are good but one is better and more modern than the other.

JohnL

[hellosailor]

Amgine-
"Yep! but in order to program the calculator (or whatever) I'll have to learn more about how to calculate the celestial, which is what I'm really trying to do -"

Yes and no. Some of the classics like Mixter's "Primer of Navigation" will explain all the logic to you. But really programming a calculator means knowing that logic, converting it to the programming logic that calculator uses, checking for programming errors, and then...getting the perpetual almanac information into the calculator as well.

You'll have a fine understanding of it, but I'd argue that a good navigation text or class (many planeteriums used to offer them) would give you the same understanding without having to adapt it to the calculator. And, the Palm gives you the opportunity to do things like enter data in fields, instead of by steps or memory locations. Still, if you enjoy writing programs...

[SkiprJohn]

StryGaldWir,

Celestial will let you down if you can't see. You can't see stars. You can't see the North Star or just can't do anything. If you can't see the sun or moon or anything then it is no good. Once you gain the skills of celestial and can combine it with DR you are pretty much in the days of early 80s. If you admit that people who sailed in the '80s were much smarter than you are then ok, GPS is the only way you can navigate.

I'd suggest that everyone who goes offshore at least have a rudimentary idea of what celestial navigation is about. You don't need to be an expert, just know what it is about.

Regards,

JohnL

[Thermal]

What, no option to deploy liferaft and abandon ship?

[LtBrett]

Can I answer "All of the above?"

I like redudancy. I also like to know exactly where I am, especially in unfamiliar waters near land. If my all my electronics went out, I would of course shift to DR. I would be very nervous if in unfamiliar waters close to shore, as DR is inherently inaccurate and celestial nav only gets you within a mile or so of where you're at, assuming you've got a horizon and some stars to shoot (which implies it's night time, further adding to my unease). I think it is an excellent idea to call the Coast Guard if you are transiting an unfamiliar inlet and want some accurate local advice. BTW, if I weren't near land, the pucker factor decreases greatly and I'll calmly pick up my sextant.

Brett

[hellosailor]

Brett-
"I think it is an excellent idea to call the Coast Guard if you are transiting an unfamiliar inlet and want some accurate local advice. "
With the USCG, your mileage may vary. Cases in point:

-Years ago setting out from Newport, we needed a good chronometer hack and had no ready source for one. Didn't know any local time numbers, the internet hadn't been invented, and we didn't have a computer or modem to call the USNO. Called the USCG and got back "around seven thirty" which was several minutes off.

-Somewhat less years ago, tried to confirm the time of slack current in an inlet known to have too much of it. "We're sorry, we can't give you that information, we can't be responsible if something happens to you if it is incorrect."

--And more recently, we asked a USCG station for condition in another inlet, because we were coming in disabled and would only risk it if conditions were good. We knew the timings--but not the effects of the weather at that time, the inlet was one of those "check for adverse conditions" places. In that case, the USCG station (across from the inlet) was soo busy they couldn't take a look at it, couldn't ask a boat crew (all had been out to sea for hours) what it was alike, but five hours later as we were getting ready to enter, the boat crew had finished off their list of bigger problems and actually escorted us in--still not knowing the conditions, just sure THEY had enough power to deal with it for both of us. (And they did, the boat crew were true professionals in every way.)

But answering questions on the phone? Nah, they just often don't have the staff for that. At a USCG station today the "communications watch stander" may literally be a volunteer manning the VHF and the phone, without any further information to give you. Congress just won't fund them for the personnel they need to simply do the whole job!

[unbusted67]

Aren't you supposed to call the Army Corp of Engineers in some places? I know the Southern passage to Woods Hole has a note about that on the chart. What's the story with that?