Lifeboat Navigation

[Adelie]

Originally Posted by colemj

OK, so how about my statement that few people even know how to use one?



And no one has answered the question about just what one would DO with a sextant in a liferaft. One is not navigating in a liferaft.



Seems like something that could be broken and poke a hole in the raft to me. Certainly the $60 would be better off spent on other useful items.



Mark

Annual and long term almanacs come with instructions. With time to kill on a lifeboat I am sure one could figure it out.

The original scenario said lifeboat not liferaft. In a liferaft even a GPS would be pointless. I'm a raft you push the button a wait for someone else to come and save your sorry butt. Unless you are in Indonesian waters where they didn't used to send the Coast Gaurd out for their own people let alone foreigners. Not sure if that is still the case.



Adelie

[colemj]

Originally Posted by Adelie

Annual and long term almanacs come with instructions. With time to kill on a lifeboat I am sure one could figure it out.

Even on a lifeboat, after just abandoning ship, are you going to be so bored for the next 1-4 days that you would want to learn celestial navigation?

How many carry a lifeboat instead of a liferaft? If so, do you plan to row it toward a destination if you find yourself in it? Does it have sails, and if so, how well does it sail? In navigating it, will knowing your approximate position every few hours be more helpful than just looking at a hand compass?

And it has to be a real lifeboat - counting on a rowing dinghy or the like to save your butt is sillier than counting on navigating a lifeboat to land.

Mark

[David M]

I don't see any point in having any older navigation tools in a vessel you can't navigate anyway. You don't really need to know where you are so long as your rescuers know where you are, and that is done with an EPIRB or a sat phone and a GPS.

[Jammer Six]

Originally Posted by colemj

Actively moving doesn't help SAR efforts.

Now, there's the best reason I've read here.

That said, if you could establish radio contact, by whatever method, I would think that the more position information you could give them the better.

[Ex-Calif]

"Liferaft log - Day 22. Sun unbearably hot. Haven't caught anything to eat today. Water maker membrane seems to be plugged or giving up. Only made a 1/2 cup of water. Sleeping more and more. Saw a plane at about 30 degrees azimuth this morning, fired last flare, no response. I think I'm dying. Sure wish I had a sextant."

[Terra Nova]

Long before GPS, a 21-year old friend provisioned his 29' sailboat, bought a plastic sextant and a book on celestial navigation, and set out, single-handed, for Hawaii, from Los Angeles, learning to navigate on the way. Since then he did the same trip, and return, several times.

It's not that hard. Even girls do it.

[colemj]

Originally Posted by Jammer Six

Now, there's the best reason I've read here.

That said, if you could establish radio contact, by whatever method, I would think that the more position information you could give them the better.

You establish radio contact with your primary epirb. That sends your position information. Failing that, you establish radio contact with your secondary epirb, which also sends your position information.

If you establish radio contact in any other way, a gps would be miles ahead of a frightened, exhausted, possibly injured and low on sleep sextant fix. Even by an old hand with a sextant.

On board, we have portable GPS data from our handheld DSC VHF, our two HH GPS's, two cameras and two iPads (in addition to EPIRB). Certainly one of those 7 devices would make it into a liferaft with us.

Mark

[Jammer Six]

Originally Posted by colemj

Certainly one of those 7 devices would make it into a liferaft with us.

And if everything, and I mean everything, goes into the water first, will one of them be waterproof?

If you have no epirb, (I don't) you rely on electronics?

Wet electronics?

Or do you have a way to guarantee that one of your devices won't get wet, or at least won't be damaged by being four feet under for a couple minutes?

[Jammer Six]

Actually, my handheld VHF is submersible, so I assume yours is.

So it would work, but would it have the power for life and death?

[Ex-Calif]

Originally Posted by Jammer Six

And if everything, and I mean everything, goes into the water first, will one of them be waterproof?

If you have no epirb, (I don't) you rely on electronics?

Wet electronics?

Or do you have a way to guarantee that one of your devices won't get wet, or at least won't be damaged by being four feet under for a couple minutes?

I think if one trades taking a sextant and leaving behind the EPIRB they are not making the best trade.

Waterproof GPS? Not an issue. Why presume the vhf will survive and the GPS won't?

Providing position data to SAR is a good idea but from a small raft what is your accuracy? 5 miles? 10? 25 square mile search box up to 100 square mile search box.

I have done SAR - it is not easy to spot a target on the water or on the ground.

I'll go for 15 meter position accuracy.

And are we now talking about navigation still or position and communication.

Knowing where one is is the first step of navigating. What about charts? Paper (wet) laminated how many?

Take the handheld GPS with the charts built in.

The absolute only reason to trust your life to celestial navigation in a liferaft situation is... Well there isn't one.

When you leave the yacht - leave sentimentality on-board and let it sink.

I also did a 5 day survival school - A lot of things you read about and think you can do? You can't. They are hard and you can't depend on them. We were in the mountains of So. California in the Summer. I couldn't make water (water still). I couldn't catch game. I did catch a bug in my still and ate it under the instructors advice. I don't think one bug a day is going to appreciably extend my life.

They let us "newbies" go 24 hours without water (once our stored ration was depleted) I though I was going to croak (but my throat was too dry - LOL) - the lesson was not to make water - the lesson was what happens when you don't or can't.

Someone above quoted raft time in hours these days - If 2 EPIRBs gets me out of the raft in 2 days - I'm gonna take that first.

Sextant won't die? So what if no one can find you...

OK - Sorry for the rant...

[colemj]

Originally Posted by Jammer Six

And if everything, and I mean everything, goes into the water first, will one of them be waterproof?

If you have no epirb, (I don't) you rely on electronics?

Wet electronics?

Or do you have a way to guarantee that one of your devices won't get wet, or at least won't be damaged by being four feet under for a couple minutes?

Three of them are waterproof. Some of the non-waterproof ones are in water tight containers in the ditch bag.

I can't imagine why anyone would go cruising without an EPIRB, let alone have a liferaft/lifeboat, yet not have an EPIRB.

I guess if one goes ocean cruising without an EPIRB, but does have a lifeboat, and doesn't have any electronic rescue stuff, then maybe a sextant makes some sense. If only to keep one's mind settled while they died.

Mark

[colemj]

Originally Posted by Jammer Six

Actually, my handheld VHF is submersible, so I assume yours is.

So it would work, but would it have the power for life and death?

A VHF isn't very useful unless you are within a couple of miles of a ship that can receive your transmission.

Aside from that, ours also takes AA batteries and a brick of those are with the VHF in a waterproof container in our ditch bag.

Mark

[Ex-Calif]

Originally Posted by colemj

I guess if one goes ocean cruising without an EPIRB, but does have a lifeboat, and doesn't have any electronic rescue stuff, then maybe a sextant makes some sense. If only to keep one's mind settled while they died.

Mark

Sarcasm is a meal best served cold.

That one really did make me Laugh Out Loud.

Thanks!

[Adventurebound]

[QUOTE=colemj;1573787

I guess if one goes ocean cruising without an EPIRB, but does have a lifeboat, and doesn't have any electronic rescue stuff, then maybe a sextant makes some sense. If only to keep one's mind settled while they died.

Mark[/QUOTE]


That's got it nailed. If you are solo and fall overboard, actually the most useless items now in your life is your sailboat, the warm comfortable bed, your food and water, and your Epirb, as all drifts away. I always have a PLB stapped to my belt under my life jacket.

[Svanen]

sneuman is correct: a sextant is not "fairly useless without reduction tables, chrono, charts, etc." On the other hand, I tend to agree with Mark that there are higher priority items for inclusion in a liferaft (or lifeboat), especially for GPS-reliant mariners who don't know navigation.

Personally, I have a healthy suspicion of 'one-size-fits-all' lists, especially for ditch bags, first aid kits, or similar emergency gear. Far better to take the time to choose the individual contents yourself, and to restrict them to items that (i) after careful consideration, you think will meet the particular demands of the situations that you are most likely to encounter, and (ii) you are qualified to use without additional instruction. If there is a disconnect between (i) and (ii), seek appropriate instruction while there is still time.