Sextant

[Steve Pope]

Hello sailor, which Nav program do you use on your Palm?
Steve.

[charley]

Hello sailor, which Nav software do you use for the Palm? Thanks

[hellosailor]

Steve-Charley-
Charles Manson's "Navigator" package.
e-mail-info@PilotNavigator.com

He's got a very reasonable package that does piloting, sailing, and sight reductions and he's been providing free upgrades and outstanding support for years now. I think v.5.8 is the current version, should be available for free trial downloads from any good Palm software source. Registration was something terribly reasonable, maybe $20, and if you find something that you think could be improved--he does it.

Works on old Palms as well as new ones, so for $50-60 you can buy a Palm and software and have a nav computer that does way way much more.

[alan2]

Originally Posted by hellosailor

Charley, there are a lot of thieves on eBay and several of them are selling ornamental sextants, usually brass and usually London, either accidentally or perhaps intentionally failing to make clear that what they are selling is an ornament--not an instrument.

Caveat emptor. A good used metal sextant (Astra, ARES, Freiberger, Tamaya, any "Plath" company, etc.) is going to sell for good money and if you arent' familiar with sextants and don't know how to inspect one for damages, I'd suggest either sticking to a reputable vendor, or buying one of the less expensive metal ones, new, from a reputable vendor.

The plastic ones are plenty good enough for learning, in fact they might be better because in order to get good results you will have to check the index error every time you use it--reinforcing that habit.

There are pros and cons to all of them, and pretty much everything can be considered both good and bad, i.e. "light" vs "heavy". Any of them, even the cheap Davis, will help you make landfall if everything else fails. The better models with more precision, if you can take advantage of it, are worth their higher prices more if you can afford to invest in an intellectual exercise, i.e. if you really want to compete with yourself to see if you can get a fix within two miles (considered a tight fix from a small boat at sea) instead of five or ten miles.

Some planetariums and Power Squadrons give celestial nav classes, if you can track one down the instructor may be willing to talk to you and give you some hands-on time before you buy anything.

Cel nav, to me, is an interesting intellectual exercise. I started with a Davis Mark 3, then graduated to a Davis Mk. 15, purchased on Ebay, it was EXACTLY as represented, so far as I can tell. About a year ago, feeling at the time, "flush", possibly foolish, I purchased an Astra 111B. Very nice instrument and about 1/3 the price of Plath or Tamaya sextants via Celestaire. My Astra appears to be extremely stable respecting index error, usually about .1 minute "on". In any event, I check index error every time I take a sight, it's a matter of SECONDS, literally. Any error found can be corrected for in sight reduction, when it's slight, or adjusted out in the event it gets large, that is minutes of arc. One of the nicer things about Celestial navigation is that it gets one out in the sun and what might be "fresh air". It's also a good excuse for going to the beach.

[Sam Plan B]

I searched ebay a few months ago for a sextant. The brass ornimental sextants are there a'plenty. I settled on a US Navy sextant manufactured in 1945. It cost about $200 as I recall. It came in a nice wood box with all the adjustment tools and a telescope too. It looked new as if it had been in someone's attic for the last 60 years. You can find deals but you have to go back again and again. Plastic sextants are okay, I suppose. But for a little more you can have a real work of art aboard.

William F. Buckly produced how-to video on celestial. I think it is still available through Celaistaire Celestaire - Navigation Equipment.

[sailr69]

you all are quite funny, sextant use in itself, is very easy, on a small rocking boat, are you using upper limb or lower limb? how do use use height of eye? refraction, sextant error. if you can even use a sextant properly to determine if you are in a five mile error you would be doing fine. but the real issue is, what are you using to calculate your position. are you using air navigation tables or Marcq St. Hilaire intercept method.
this takes a norris book of tables and knowledge of spherical trig. to even get to first base. to reduce a sight takes 5- 15 minutes for a skilled navigation officer.
a navigational day consist of morning sun, noon sun, afternoon sun and evening stars. to plot all this takes a considerable amount of time.
to shoot any star, you need to identifiy it, how are you going to do this? star chart? how are they used? That takes a lot of learning.this can go on and on and on. You got plotting paper on board? ever try plotting positions on board a rocking boat? Your DR positioning had better be damn good. hgt calculated means nothing if you do not have a decent DR. It is better to have a couple of good GPS's unless you want to spend several hours a day navigating with a sextant and DR'ing. I have done this, I know.

I am sorry to keep ranting about this, but it is a very involved navigation system. not easily learned. as a matter of fact; it was a military secret for many years. The US finally published it to the Chagrined Brits and French.

good night all!

[daddle]

Originally Posted by maxingout

A bubble sextant works great anywhere.

Except at sea where the bubble feature is 100% useless.

[Lodesman]

Originally Posted by sailr69

you all are quite funny, ...

Your DR positioning had better be damn good. hgt calculated means nothing if you do not have a decent DR.

I find it funny that someone will resurrect an old thread just to piss on people. The statement about the DR tells me you don't really know what you're talking about. Of course you should keep an accurate DR, for its own sake; that's just good navigational practice. I can't speak to using Air Nav tables, but using the Marcq St Hilaire method, you work from an Assumed Position - the DR only has to get you into the ballpark. If you`re comfortable working on a small scale, you can start with a DR hundreds of miles away - you`ll just have very long intercepts.

[Alecadi]

Originally Posted by sailr69

I am sorry to keep ranting about this, but it is a very involved navigation system. not easily learned. as a matter of fact; it was a military secret for many years. The US finally published it to the Chagrined Brits and French.

good night all!

Do you mean that the use of the sextant was a military secret use only by the US Navy??
If it is so, please revised your history books.
I'm sure I misunderstood you.

[sneuman]

Originally Posted by sailr69

you all are quite funny, sextant use in itself, is very easy, on a small rocking boat, are you using upper limb or lower limb? how do use use height of eye? refraction, sextant error. if you can even use a sextant properly to determine if you are in a five mile error you would be doing fine. but the real issue is, what are you using to calculate your position. are you using air navigation tables or Marcq St. Hilaire intercept method.
this takes a norris book of tables and knowledge of spherical trig. to even get to first base. to reduce a sight takes 5- 15 minutes for a skilled navigation officer.
a navigational day consist of morning sun, noon sun, afternoon sun and evening stars. to plot all this takes a considerable amount of time.
to shoot any star, you need to identifiy it, how are you going to do this? star chart? how are they used? That takes a lot of learning.this can go on and on and on. You got plotting paper on board? ever try plotting positions on board a rocking boat? Your DR positioning had better be damn good. hgt calculated means nothing if you do not have a decent DR. It is better to have a couple of good GPS's unless you want to spend several hours a day navigating with a sextant and DR'ing. I have done this, I know.

I am sorry to keep ranting about this, but it is a very involved navigation system. not easily learned. as a matter of fact; it was a military secret for many years. The US finally published it to the Chagrined Brits and French.

good night all!

I thoroughly disagree. I taught myself celestial over the winter and it was much less difficult than I thought it would be. The simplest noonsite requires no tables and no spherical trig. - just a nautical almanac and a dime-store calculator (optional).

Lucky for me, I already knew a dozen bright stars in the night sky. This is NOT difficult to learn. It takes a few nights of practice using constellations and asterisms to guide you.

In short, celestial is not black magic. Remember: there was a time when every snotty nosed little brat behind the mast was required to learn it - many of them with scant formal schooling.

[chala]

Originally Posted by sailr69

[FONT=Arial][SIZE=3]to shoot any star, you need to identifiy it, how are you going to do this?
good night all!

Have a go. After a few days you will find out it is quite easy. Dial your sextant, look in the right direction and just adjust.

[boasun]

Used Sextants on ships in my maritime career, before there was GPS... Still find celestial Navigation an excellent means of keeping your GPS honest. also Good mental exercise and When your batteries die you can still find your way across the oceans.
Of course you could use a astrolabe or a cross staff, but a back staff would be better because you are not looking directly into the sun. One reason there was a few blind navigators in the very early days of shipping.

[alan2]

sailr69:

There is most certainly something in what you say, however note the following. BTW, I'm not a boater, I know people who are, ocean racing and such as that so while GPS is great, I have a handheld, basic Garmin etrex, and electronics, when they are working certainly take care of a whole lot of drudgery.

That having been said, were I an ocean going type, any boat of mine, while it might be equipped with GPS and or other electronics, would not venture out of sight of land absent the following:

1. At least one properly aligned sextant.
2. A set of sight reduction tables, there are a couple, depends on one's preference, W.F. Buckley Jr. liked the Air Navigation Tables (H.O. 249) I believe. As I "practice celestial navigation", I use the Nautical Almanac, which I'm fairly familiar/comfortable with.
3. Sight Reduction Forms, they are handy and don't take up a lot of space.
4. At least one scientific calculator or "electronic sliderule, with spare batteries, or a solar powered type, I'm partial to an old HP 11C, which I've had for years. I get nothing from HP for the "testimonial".
5. An accurate, reliable time piece, again at least one, I like the Casio G Shock, again Casio doesn't know me from Adam.

I would also hope that the electronics never went "tits up" as sometimes happens, but as has been observed, "stuff happens".