"Gordon" wrote in message
...
Does anyone doubt that Columbus or Slocum would have passed on using a
GPS had it been available?
G

Yes. ;-)

"Scotty" wrote in message
. ..

"jeff" wrote in message
...
wrote:


I carry a lead line, and use it on occasion, usually when
moored in very
tight quarters.

when anchoring in shallow water, I use my boat hook to check
the bottom.

SBV


Either you carry a very long boat hook... or your definition of shallow is
different from most sailors.

wrote in message
...
On Sun, 16 Sep 2007 22:06:00 -0000, otnmbrd
wrote:

Larry wrote in news:Xns99ADAD78CF807noonehomecom@
208.49.80.253:



Celestial Navigation, while quite romantic and "salty", are no longer
necessary for worldwide navigation.

Larry

No longer necessary, true, but for a long distance sailor the ability to
use it can/could come in handy for many reasons.
Hell, we could say that the Mark 1 eyeball or soundings are no longer
necessary, but we still use them and find good reasons to do so.


You know it's kind of funny. Everyone talks about using an archaic
method of determining position and never mention using either a lead
line to determine depth or a chip log to determine speed.

How come all the advocates of a relative low tech method of
determining a position never mention that the system is unusable for
navigation in tight spaces, narrow channels, etc. and dead reckoning
or taking sights or measuring depth will be necessary.

I never hear anyone recommend having a lead line on board in case your
electronic depth sounder fails or a chip log mounted on the stern
pulpit in case your electronic speed log fails.

I am not saying that one shouldn't learn celestial navigation or not
carry extra life jackets but it is no longer a necessary skill.




Bruce in Bangkok
(brucepaigeATgmailDOTcom)


Actually, the lead line is something we talk about during some of our
classes...


--
"j" ganz @@
www.sailnow.com

wrote in news:futse3pgo9nvn157klj3rkodjqh8gv0777@
4ax.com:


You know it's kind of funny. Everyone talks about using an archaic
method of determining position and never mention using either a lead
line to determine depth or a chip log to determine speed.

How come all the advocates of a relative low tech method of
determining a position never mention that the system is unusable for
navigation in tight spaces, narrow channels, etc. and dead reckoning
or taking sights or measuring depth will be necessary.

I never hear anyone recommend having a lead line on board in case your
electronic depth sounder fails or a chip log mounted on the stern
pulpit in case your electronic speed log fails.

I am not saying that one shouldn't learn celestial navigation or not
carry extra life jackets but it is no longer a necessary skill.




Bruce in Bangkok
(brucepaigeATgmailDOTcom)


Taking this back to the original post...... the poster was asking about
offshore navigation (my assumption) and the benefits of learning and having
the ability to use celestial.
A cheap sextant and a few books is an easy way to add a layer of possible
solutions should Mr. Murphy rear his ugly head.

BTW.... watching a show on offroading, the host suggested using one of
those vacumn packing/sealing machines with the plastic bags to seal parts
against dirt and water/weather..... should think this would have a great
potential on boats also... especially the offshore cruiser.


LOL....I know..... how'd I jump this far on subject matter?

Don White wrote:

I carry a lead line, and use it on occasion, usually when
moored in very
tight quarters.
when anchoring in shallow water, I use my boat hook to check
the bottom.

SBV


Either you carry a very long boat hook... or your definition of shallow is
different from most sailors.


I used my boat hook several times summer - since my boat only draws 3
feet and the hook extends to over 8 feet, I don't see where the problem
would be. There have been times in the Keys when I stood on the bottom
to see if we'd have enough at low.

wrote

I was just told by a friend that I should learn celestial
navigation before sailing around the world because
GPS devices don't work that well in the middle of the
ocean and can malfunction if they get wet, etc.

Does my friend have a point even if I intend to bring
3 independent GPS systems with me ?

How about if I just get a cheap sextant and the book
"Celestial Navigation When Your GPS Fails" and
bring them with me ?

The information supplied by your friend perhaps could use some updating.

The basic GPS system is very reliable and is used worldwide by many,
including the aviation industry.

Small, battery operated units, likely to be found on small boats are more
likely to fail than those on aircraft; however, having multiple back up
units on board addresses this issue.

Being able to use a low cost sextant as the last opportunity navigation
device, certainly has it's advantages, and basic celestial navigation is not
difficult to learn.

SFWIW, I have a new, still in the box, Davis, Mark15 sextant, complete with
artificial horizon that I'm about to put on Craig's list.

If you are interested, contact me off list.

Lew

If you are going to use a sextant, you need a reliable clock.

The most reliable, accurate clock available today is a GPS receiver.
So pack a spare GPS receiver along with the sextant. As an added
advantage, you can always cheat and check your fix against what your
"clock" tells you :-)
--

On Mon, 17 Sep 2007 13:55:25 -0400, jeff wrote:

Don White wrote:

I carry a lead line, and use it on occasion, usually when
moored in very
tight quarters.
when anchoring in shallow water, I use my boat hook to check
the bottom.

SBV


Either you carry a very long boat hook... or your definition of shallow is
different from most sailors.


I used my boat hook several times summer - since my boat only draws 3
feet and the hook extends to over 8 feet, I don't see where the problem
would be. There have been times in the Keys when I stood on the bottom
to see if we'd have enough at low.


Well, if you have six foot tides you might have a problem :-)


Bruce in Bangkok
(brucepaigeATgmailDOTcom)

On Mon, 17 Sep 2007 16:29:01 -0000, otnmbrd
wrote:

wrote in news:futse3pgo9nvn157klj3rkodjqh8gv0777@
4ax.com:


You know it's kind of funny. Everyone talks about using an archaic
method of determining position and never mention using either a lead
line to determine depth or a chip log to determine speed.

How come all the advocates of a relative low tech method of
determining a position never mention that the system is unusable for
navigation in tight spaces, narrow channels, etc. and dead reckoning
or taking sights or measuring depth will be necessary.

I never hear anyone recommend having a lead line on board in case your
electronic depth sounder fails or a chip log mounted on the stern
pulpit in case your electronic speed log fails.

I am not saying that one shouldn't learn celestial navigation or not
carry extra life jackets but it is no longer a necessary skill.




Bruce in Bangkok
(brucepaigeATgmailDOTcom)


Taking this back to the original post...... the poster was asking about
offshore navigation (my assumption) and the benefits of learning and having
the ability to use celestial.
A cheap sextant and a few books is an easy way to add a layer of possible
solutions should Mr. Murphy rear his ugly head.

BTW.... watching a show on offroading, the host suggested using one of
those vacumn packing/sealing machines with the plastic bags to seal parts
against dirt and water/weather..... should think this would have a great
potential on boats also... especially the offshore cruiser.


LOL....I know..... how'd I jump this far on subject matter?


Vacuum packing. Quite a number of people I meet use this system
both for food and for things that they don;t want to deteriorate in
the damp atmosphere on a boat. Apparently works great.

The original poster was asking if he HAD to learn celestial before
starting off on his world tour and frankly (I'm about half way around
on most people's trip) I have never talked to anyone who actually used
a sextant to navigate. I have talked to people who had one aboard but
if you ask them whether they actually use it they sort of grin and
admit that "no, they don't".






Bruce in Bangkok
(brucepaigeATgmailDOTcom)

wrote:

I used my boat hook several times summer - since my boat only draws 3
feet and the hook extends to over 8 feet, I don't see where the problem
would be. There have been times in the Keys when I stood on the bottom
to see if we'd have enough at low.


Well, if you have six foot tides you might have a problem :-)


Bruce in Bangkok
(brucepaigeATgmailDOTcom)

Here's the spot where I used the boat hook (Misery Island, Salem Bay, MA):

http://www.sv-loki.com/IMGP1025.jpg

The tides there are about 10 feet. The spot where we're at in the
picture has about 4 feet under the keel at low, but the previous night
we were on the red mooring on the far right and early in the morning I
determined that we were headed for a deficit of an inch or two (because
of an extreme low), so we moved over.

In the Keys, of course, the tides are generally two feet or less.