Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 29-08-2009, 07:11   #46
Registered User

Join Date: Feb 2009
Posts: 110
Quote:
Originally Posted by barnakiel View Post
There seems to be a bit of 'urban legend' thing going on about the sextant.. (see remainder of post)
This post pretty well sums up my thoughts and experience too.
clearsea is offline   Reply With Quote
Old 29-08-2009, 08:50   #47
Registered User
 
Talbot's Avatar

Join Date: Jun 2004
Location: Brighton, UK
Boat: Privilege 37
Posts: 3,741
Images: 32
Quote:
Originally Posted by clearsea View Post
This post pretty well sums up my thoughts and experience too.
Yes, Barnekiel has hit the nail very accurately on the head.

Furthermore, I find it amusing that some people talk about the need for a sextant after a lightning strike, and then discuss use of electronic calculators to do the maths.
__________________
"Be wary of strong drink. It can make you shoot at tax collectors - and miss."
Robert A Heinlein
Talbot is offline   Reply With Quote
Old 30-08-2009, 23:33   #48
Registered User
 
ka4wja's Avatar

Join Date: May 2007
Location: Florida
Boat: Catalina 470
Posts: 2,592
Yes, I still do use my sextant!

To answer the original question.....
Yes, I still do use my sextant.....
I use my late father's 40+ yr old Tamaya Jupiter, with an accurate quartz watch, Almanac, and Air Nav Tables.....
(My Dad was the one who taught me originally...but I read the books as well, and have used my skills over the years.....)
And, although I also do use GPS (as primary), I use my Ritchie steering compasses and paper charts as primary navigation tools....with sextant, etc. as back-up....

Although, I've shot the moon on a few occassions, I'm mostly a "sun-sight" celestrial navigator....
Nowadays, with GPS, I plot my position (GPS fix) on my paper charts every few hours, etc.....
And, using my sextant, typically do an early morning shot, and a noon shot, reduce them and plot my LOP and est. position....every few days or so, when on an ocean passage/crossing the Atlantic....

This is mostly for fun and practice......
And, I'm not sure if it's inherited or not, but as long as I could see the sun, I've never had a problem shooting a sight at sea.....I use the simple 4x40 scope, and even in rough seas, I've been able to shoot pretty well....
Comparing my LOP / DR est. position with my GPS fix, I typically find I'm within 2 miles with sunny skies and slight seas.....and only a bit worse (within ~ 3 - 4 miles) in rough weather and/or cloudy skies....
Maybe not as good as some of you....but not bad...

And, for those who think $$$ should be spent on "back-up" GPS's.....
I do have them as well......1 primary Raymarine and 1 spare Raymarine.....1 primary Garmin and 3 spare Garmin's, along with a lot of AA batteries for them....(spare raymarine and one spare garmin in anti-static bags, wrapped in multiple layers of alum foil, just as precaution...)

{ One of my first officially necessary celestrial nav uses....was back ~ 30 years ago, sailing across the Atlantic (as a teenager), I was the navigator.....and I used this sextant, quartz watch (with WWV), almanac, and tables....and did all calculations long-hand.....this was, of course, pre-GPS......
And, darned if Barbados wasn't exactly where it sould've been after 3000+ miles..... }




Quote:
Originally Posted by barnakiel View Post
There seems to be a bit of 'urban legend' thing going on about the sextant, so:

- if Cook (but why just Cook?), if Cook (had) had GPS he would have used it, and probably he would have known (as he did) to use the sextant,

- using sextant / almanac IS easy - I can take the sight and calculate my LOP in about 10 minutes (a bit longer if no calculator available either), of course one has to spend some time&effort learning, but all sailing is learning no matter how much experience you already have, and yes - to me, it is fun,

- a single bad lightning bolt in your vicinity and you may end up with ZERO electronics, a single bad day for the US govt and they can switch off the GPS, - PLS read the most recent info on the state of GPS satellites and you will know why the 'new' Loran is being beefed up and introduced as backup,

I use the GPS a lot, and not just to get the fix. And I love and adore all the other things on board that blink and beep. But to me crossing an ocean without the sextant/almanac would be asking trouble. I understand that along the coast and for shorter passages sextant is not necessary (I never take mine out at such times anyway).

And finally, I hope I will make someone very angry when I state that I found most of those sailors who blah about the sextant being of no use next to ingnorant when it comes to proper use, terminology and limitations of the GPS too.

b.
And, barnakiel, I couldn't written anything better myself!
I agree with you completely!

Fair winds to all....
John
ka4wja is offline   Reply With Quote
Old 22-02-2010, 15:41   #49
Registered User
 
Svanen's Avatar

Join Date: Nov 2009
Posts: 175
Quote:
Originally Posted by Talbot View Post
Slocum used an old tin clock which at one stage he boiled in water and then soaked in oil
If I remember correctly, he relied primarily on dead reckoning, with noon sights for latitude; so an accurate timepiece was not required. I could be wrong, though.

I have sent you a pm asking for your sight reduction work form.
Svanen is offline   Reply With Quote
Old 22-02-2010, 16:25   #50
Registered User

Join Date: Feb 2010
Posts: 120
The last time I used a sextant it was for my circumcision!!! And believe it or not.....but it hurt like a bi*ch!!!!!
dniello is offline   Reply With Quote
Old 22-02-2010, 18:06   #51
Registered User
 
Laidback's Avatar

Join Date: Jun 2007
Posts: 853
Quote:
Originally Posted by dniello View Post
The last time I used a sextant it was for my circumcision!!! And believe it or not.....but it hurt like a bi*ch!!!!!
dniello,
What a pity that your contributions to CruiserForum have degenerated to the level of smut in the above quoted post. Without humor or value.
Laidback is offline   Reply With Quote
Old 22-02-2010, 18:58   #52
Registered User

Join Date: Mar 2009
Location: Houston
Posts: 149
Many times I've wished I had my 1977 model Zeiss Freiberger Yachtsman, but alas I sold it in a fit of raising cash.

However, I am very pleased to say I bought a pre-owned Astra IIIb this past weekend. I look forward to re-learning the whole thing, and seeing what sort of software there might be that would simplify the data lookup and calculations. If there isn't, that's okay with me anyway.

Quirky and quaint I suppose, but I have enjoyed shopping for a sextant, and gotten to where I envision a little collection of the darn things.

Now, what's this "GPS" thing ya'll are talking about? Must be one of those new-fangled electric things.
Jim D is offline   Reply With Quote
Old 23-02-2010, 13:18   #53
Registered User
 
Rockin_Rick's Avatar

Join Date: Oct 2008
Location: Newport Beach CA
Boat: Irwin 37 Center Cockpit MKV
Posts: 18
Thumbs up Join your local USPS and learn

The US Power Squadron has a gret series of two classes on Navagation with a Sextant and Almanac. They spend one full 10 week class on just sun sights (Jr Nav)and the second on all the rest of the Planets and stars (Sr. Nav.). It will really put you through the paces but when you pass you will know.

Rick
S/V Footprints
Long Beach
Alamitos Squadron
Rockin_Rick is offline   Reply With Quote
Old 23-02-2010, 18:22   #54
Senior Cruiser

Cruisers Forum Supporter

Join Date: Oct 2008
Location: Coos Bay, Oregon
Boat: Valiant 40 (1975)
Posts: 4,073
Rick, how does one old cruiser get into these classes. I thought the power squad was like the sea scouts- for young bucks.
s/v Beth is offline   Reply With Quote
Old 24-02-2010, 11:59   #55
Registered User
 
Rockin_Rick's Avatar

Join Date: Oct 2008
Location: Newport Beach CA
Boat: Irwin 37 Center Cockpit MKV
Posts: 18
How to Join USPS

It's easy just go to USPS.org and find your local squadron site. They post all the classes and events. No, they are mostly old salts like us not kids.
It's really reasnonble and you can't beat the quality of the classes at any price. They will send your sight log to HQ before they even will allow you to take the exam. It's open book and you have over a month to complete it.

Rick
Rockin_Rick is offline   Reply With Quote
Old 24-02-2010, 12:20   #56
Moderator Emeritus
 
nigel1's Avatar

Cruisers Forum Supporter

Join Date: Oct 2009
Location: Manchester, UK
Boat: Beneteau 473
Posts: 5,600
Theré are some neat methods of position fixing with a sextant. Certain times of the year you can get a good fix with the sun and venus, (need to pre-work venus to find it on the horizon). Another nice one is when your latitude is close to the suns declination. You can skip all the math and basically plot the suns geographical position on the chart (Dec as Lat, and convert Local Hour angle to Longitude), then using the zentih distance as measured, draw off a position circle. Taken just before and just after mer pass it gives a good fix.
When I was going through my merchant navy apprenticéship we were forced to study Principals of Celestial Navigation, at the time, beng 16yrs old and better things to do, it was a PITA, but looking back, glad I did it, as you get to undestand how all those shiney things in the sky let you find your position.
Back then calculators were not allowed in exams, nor were the sight reduction tables, but with practice, a sight could be worked out in 5 mins using the almanac and nories tables.

Hey, Talbot, if your reading this, see your in Stavanger, I'm on the big blue tug boat parked on the Bekhuskaien (the outboard of the two tugs) If you want a look around call us on46 91 51 72
__________________
Nigel
Beneteau 473
Manchester, UK
nigel1 is offline   Reply With Quote
Reply

Tags
sextant


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Inverted Sextant Scope clausont Navigation 5 24-05-2015 08:09
Sextant... blackjack Navigation 120 07-09-2013 08:16
Sextant charley Navigation 42 15-06-2011 16:39
Sextant for sail over40pirate Classifieds Archive 4 20-07-2008 02:50

Advertise Here


All times are GMT -7. The time now is 00:35.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.