The New and Improved Celestial Navigation Poll

[River Cruiser]

Being on a river I haven't seen the need just stay in the channel & you can't get lost.

[Celestialsailor]

If my GPS's are fried, I will use the "Captain Ron" method of navigating. That is to just pull in somewhere and ask directions...

[rubyjean]

Originally Posted by Celestialsailor

If my GPS's are fried, I will use the "Captain Ron" method of navigating. That is to just pull in somewhere and ask directions...

My wife told me that men don't ask for directions....:bangh ead:

[rebel heart]

Originally Posted by deckofficer

Eric,

I'll admit it wouldn't be pleasant to be in the middle of a passage and get all your electronic devices fried by a lightning strike. Since all the heavy books have been transferred to CD, (which I just discovered yesterday by clicking on the banner ad for this thread) I would carry my sextant, but lets address the folks that don't know how to celestial navigate. One could always from their last known position, DR to the nearest land mass and from there take land bearings to determine where they are and get to a port. I wouldn't want to navigate that way, but it is doable. Of course the auto pilot is fried too, but unless I'm in very light winds, or no wind and motoring, I would be using the vane anyway.

When I was in the Navy I worked as a weapons guy, and we would do target motion analysis on all of our contacts via the computer. Big massive heavy computers that were powered by redundant buses and completely hand-repairable. But there was also a guy standing behind with a grease board doing the math by hand just in the case the boat took a hit or we otherwise lost our computers. There were sound powered phones (no electricity) that could be used to instruct the torpedo guys on manual assignments, the weapons can be loaded by blocks and lines (should be one in there anyway), and the doors could be opened manually. Point the boat in the right direction, flood the tube, water activates the solid propellant system, out the door.

There was just a huge focus on never relying on your computers and the best sailors and boats were the ones that could complete mission objectives no matter the conditions. It got drilled into my head to never trust computers.

And funny enough, I've worked in software development for ten years including for a satellite company with a constellation very similar to the government's gps network.

[hummingway]

Originally Posted by deckofficer

Eric,

I'll admit it wouldn't be pleasant to be in the middle of a passage and get all your electronic devices fried by a lightning strike. Since all the heavy books have been transferred to CD, (which I just discovered yesterday by clicking on the banner ad for this thread) I would carry my sextant, but lets address the folks that don't know how to celestial navigate. One could always from their last known position, DR to the nearest land mass and from there take land bearings to determine where they are and get to a port. I wouldn't want to navigate that way, but it is doable. Of course the auto pilot is fried too, but unless I'm in very light winds, or no wind and motoring, I would be using the vane anyway.

Let's say you're at Lat 38.685510 Long -177.890625 and everything fries. If you haven't been charting your location as you go it's a pretty good chance you'll sail a long time with hitting land. Supposing you have been charting though, will DR get you to an island?

Note that location is the middle of the North Pacific.

[deckofficer]

Originally Posted by hummingway

Let's say you're at Lat 38.685510 Long -177.890625 and everything fries. If you haven't been charting your location as you go it's a pretty good chance you'll sail a long time with hitting land. Supposing you have been charting though, will DR get you to an island?

Note that location is the middle of the North Pacific.

If you asked this of a long term cruiser, you would get a better answer than I as a merchant mariner could provide, but what the hay, here goes.

I chart, so I will know my last position before losing all the electronic aids. First I would construct a chip log so that I know my speed by trailing it behind me many times during a 24 hour period. I personally would not trust my DR skills to make landfall on an island, but rather a nice big land mass like the Asian Coast. Once in sight of land I would study the coast for prominent features and find those features on my charts, take three bearings from the main feature and two others at enough of an angle for me to determine my vessel's position and continue to the nearest port by taking land bearings.

Now, I would like to hear how a seasoned, long term cruiser would do it, as I'm always up for learning new stuff.

[foolishsailor]

Originally Posted by hummingway

Let's say you're at Lat 38.685510 Long -177.890625 and everything fries. If you haven't been charting your location as you go it's a pretty good chance you'll sail a long time with hitting land. Supposing you have been charting though, will DR get you to an island?

Note that location is the middle of the North Pacific.

I would assume that anyone who does not keep their position on a paper chart would also not find value in learning the skills associated with good DR and therefore would be screwed?

[44'cruisingcat]

So far, costal cruising, haven't felt the need.

But now we're planning to head out into the Pacific, I'm thinking it would be good to know how, and have the tools available to do it.

Having the info available on CD sounds good, but if the reason I'm getting the sextant out is because lightning fried the electronics..... ummm....

[msponer]

Originally Posted by deckofficer

Now, I would like to hear how a seasoned, long term cruiser would do it, as I'm always up for learning new stuff.

Emergency Navigation is one of my favorite technical sailing books, and I feel the best in it's genre. There are a lot of neat little tricks and rules of thumb that are useful all the time (like estimating the distance from an island by how many 'fingers' it is above the horizon), and a lot of interesting techniques in the thought experiment of navigating without a sextant, accurate watch, and etc -- how to steer a straight course without a compass, estimate speed by watching bubbles, guess latitude without a sextant, estimate change in longitude by the difference in the time of sunrise, and etc.

[rubyjean]

Originally Posted by msponer

Emergency Navigation is one of my favorite technical sailing books, and I feel the best in it's genre. There are a lot of neat little tricks and rules of thumb that are useful all the time (like estimating the distance from an island by how many 'fingers' it is above the horizon), and a lot of interesting techniques in the thought experiment of navigating without a sextant, accurate watch, and etc -- how to steer a straight course without a compass, estimate speed by watching bubbles, guess latitude without a sextant, estimate change in longitude by the difference in the time of sunrise, and etc.

This book is very valueable piece of information and fun for all to read. only costs about 10 bucks..Michael..

[capn_billl]

I'm going to have to get the emergency navigation book. Let's see. I'm on a cruise ship in the middle of an ocean crossing, and it goes down in the middle of the night, due to my drinking and gambling 24 hours a day, I only have a rough estimate of my position as I come to laying in a life raft. with nothing but what I normally have on my possesion,( I always carry a compass & pocket knife, and have a home depot card embossed with a 3 inch ruler).

How can I steer the life raft, (I used a piece of flotsam as a rudder, and made a kite sail out of my clothes, and the liferafts bow line).

I might have a sextant, if I thought it could help pick up an impressionable young lady at the buffet line, but sight reduction books are right out. Making an astrolab out of a piece of wood, my home depot card, and pocket knife is more likely.

Any star sights are going to have to be memorised. Polaris, and Orion are two promenent, southern cross, and big dipper,...I would say to make this work, I need to memorise rise time for several stars or moon, and position at that time for several easy to find stars.

you should be able to get a rough position from Polaris, (latitude), plus altitude of one other star near equator, these should intersect at a point. All you need is the accuracy to hit the nearest landmass. Knowing the time of year you can take the sun as a compass. (although I can magetize almost any metal object to use, and always carry a compass)

[h20man]

Originally Posted by deckofficer

Eric,

I'll admit it wouldn't be pleasant to be in the middle of a passage and get all your electronic devices fried by a lightning strike. Since all the heavy books have been transferred to CD, (which I just discovered yesterday by clicking on the banner ad for this thread) I would carry my sextant, but lets address the folks that don't know how to celestial navigate. One could always from their last known position, DR to the nearest land mass and from there take land bearings to determine where they are and get to a port. I wouldn't want to navigate that way, but it is doable. Of course the auto pilot is fried too, but unless I'm in very light winds, or no wind and motoring, I would be using the vane anyway.

Off topic, but a side note, the members that make up the top choice, even though they stood a chance of catching a bit of flaming by their admittance of never learning, for me at least, their credibility for everything they post has gone up a notch.

I still carry the almanacs and reference volumes as print.

Using celestial navigation, as an alternate navigation procedure, I like to know I am not dependent on any electronic devices. A CD version of the reference guides is of no use if the electronics that are to read the CD are not working...

[s/v Jedi]

Originally Posted by h20man

I still carry the almanacs and reference volumes as print.

Using celestial navigation, as an alternate navigation procedure, I like to know I am not dependent on any electronic devices. A CD version of the reference guides is of no use if the electronics that are to read the CD are not working...

Come on people. I'll give it another try: in the age of exploration, a sextant was like a secret weapon and it or more primitive devices was all that was available to determine ones position. Not that there was much important about it because they did not know what was lying ahead of them... they were drawing the first charts as they went.

Ever since that day, navigators have embraced newer technologies and devices and now today the secret weapons of navigation are receivers that can work with Russian, Chinese and soon European satellite constellations in addition to the US military GPS system.

So let us assume a disaster in which a lightning strike takes out all of our electronics. Would you still have an accurate clock? Did you ever think about that? Any clock that takes a battery will be taken out by the lightning strike. I for one, must admit that I would loose all clocks aboard. Which would make my sextant only usable for the noon shot if I recall my lessons correctly (I lied.. I did get my celestial navigation paper but it's so long ago that I couldn't do it without instructions today).

So here we are and we have had this lightning strike. This does NOT put us back into the age of exploration because we are now in an emergency mode... we only need to be saved, to find safe haven and civilization; we don't need to find a West passage to India!

All we really need is a compass. On any trip I make, I only need a compass to save myself.

ciao!
Nick.

[deckofficer]

Like I said Nick, I'm glad they dropped the code requirement for the General HAM radio license, sure don't need CW anymore. I just wonder if celestial navigation will be dropped sometime in the future for Unlimited licenses? That brings me to a question for captains with a specified tonnage license, was celestial nav required for those licenses?

[hummingway]

Originally Posted by s/v Jedi

All we really need is a compass. On any trip I make, I only need a compass to save myself.

.

I wonder about that. The reason I asked about dead reckoning from the middle of the Pacific is that it strikes me that trusting your compass to get you somewhere means a long sail without a clue what's below in terms of reefs and currents and above in terms of weather patterns. 2000 nm east or 2000 nm west to a major land mass. I guess you do what you can to survive but if the GPS goes out and the clocks don't you might wish you had some means to use the sky to guide you.