Finally remembered an example... A canoe of all things.

[viking north]

The Sadler 24's and 29's were the first and as far as I know only, sailing monohulls in their size range that have positive flotation built into their two part hull construction by injecting a closed cell foam between the inner liner and outer hulls--

A yacht is not defined by the vessel but by the care and love of their owners ---

[portacruise]

Originally Posted by Schoonner

I remembered a way to make a vessel float even if the hull has filled with water. The aluminum canoes that were at summer camp so many years ago reminded me.

We had to learn to row a canoe that has capsized back to the shore. We had to go something like 300 yards with two people paddling a canoe that was completely submerged under the water and trying to roll upwards out from underneath you. (The sailboat keel would stop that nonsense.)

Could a safety device use the insides of the mast like a snorkel and inflate something like car tire inner tubes around the stem and stern of a vessel to make it float even if it were hit amidships by a rogue wave and the hatches were open?



YES, but do you want tubes INSIDE or OUTSIDE THE CABIN? Are you assuming water has flooded the inside compartment or that it will leak to the point of filling the INSIDE.


The rubber might be made like a childs balloon or something so that if It hit the bottom or another boat it would deform instead of deflate and also be somewhat self repairing to a point? (You can stick a lubricated knitting needle straight through a balloon and pull it back out without it deflating... well, you can once anyways.)


YES, there are class VI white water rafts that are made of rugged materials that would withstand tremendous impacts IF this will be going on the OUTSIDE of the boat. There have also been some inflatable pontoons that were designed to be self repairing with a liquid sealant coating all surfaces inside.

I've seen sunken fishing boats recovered with car tire inner tubes before and you can actually lift a LOT with only a pair inflated tubes.



YES, but the balance point with inflatable bags INSIDE with have to be carefully determined to keep the damaged boat UPRIGHT. ALSO all your critical gear may be damaged to the point of being an extreme danger with water INSIDE the hatch- for example the engine wiring will be sensitive to water and not be operable, also safety beacons and electronic communications might go out if not sealed carefully.



Maybe even have a snorkel for the engine so that it can be started and under water and you aren't stuck without power.



THE electronics of the ignition system would need sealing to withstand SUBMERSION otherwise the snorkel won't do any good.




Something like this:


The device could probably even be switched on using a float and lever like the thing that shuts off the water in the toilet of most homes to keep the tank from overflowing.



You might need something that is self contained and inflates quickly like an automobile safety air bag to respond QUICKLY enough. Or the system used for survival rafts. No time to look for valves, inflation tubes or wonder if everything has been maintained recently in an emergency.

Another possibility is to use several hundred/thousand tennis balls to avoid crushing the crew if the buoyancy with come from inside the cabin.

Hope comments above help.

Porta

[gonzo]

Sadler boats have a very thick foam core that provides enough flotation to make them unsinkable. It takes a lot of interior space, but is a simple solution. Inflating bags and other systems make little sense. They would need a huge amount of maintenance and care. Also, the cost would be very high, just price a self inflating life raft, which is made by the thousands. The bags in a boat need to be custom made.

[Schoonner]

Originally Posted by gonzo

Sadler boats have a very thick foam core that provides enough flotation to make them unsinkable. It takes a lot of interior space, but is a simple solution. Inflating bags and other systems make little sense. They would need a huge amount of maintenance and care. Also, the cost would be very high, just price a self inflating life raft, which is made by the thousands. The bags in a boat need to be custom made.

Ahh!! I like that foam solution!! So, they have enough reserve buoyancy that they don't sink even when swamped?!? That would make it easy to just seal off all the wiring to the engines and create snorkels so that in case of emergency, the engine could actually be run anyways for at least a few hours, or even a day or two, though if you are aboard a swamped boat that just keeps getting pummeled by waves I would imagine that hypothermia might be a problem. Extra inflated flotation might help keep you drier.

I wish I knew which boats would have this foam core, and which did not.

BTW. four wheel drive vehicles often run engines underneath water to cross rivers and such.http://youtu.be/_lBakSKg8cA (You can see the red snorkel top sticking up past the roof of the car)

[viking north]

As I prev. posted Sadler are the only monohulls in their size that i'm aware of that has this positive flotation feature. If you look them up they posted their test results when flooded and making use of the positive flotation feature-- the boat seems to still be functional as a sailing vessel and was able to sail back to home port. A great feature for blue water work in a smaller yacht for sure. Your yacht becomes your lifeboat.

[portacruise]

Originally Posted by Schoonner

BTW. four wheel drive vehicles often run engines underneath water to cross rivers and such.http://youtu.be/_lBakSKg8cA (You can see the red snorkel top sticking up past the roof of the car)

Very interesting movie clip, that's more than what I thought what sounds like a diesel engine could tolerate on the Jeep. Still, that is only few minute time period in the clip. I wonder how continuous a complete submersion could be tolerated without some problems. Also we don't know if engine problems related to the submersion developed at a later date. There must be a reason IC boat engines are run in dry engine rooms.

P.

[Schoonner]

Originally Posted by viking north

As I prev. posted Sadler are the only monohulls in their size that i'm aware of that has this positive flotation feature. If you look them up they posted their test results when flooded and making use of the positive flotation feature-- the boat seems to still be functional as a sailing vessel and was able to sail back to home port. A great feature for blue water work in a smaller yacht for sure. Your yacht becomes your lifeboat.

Cool! I will have to look at their data. This is getting really interesting. I will start drawing soon.

I don't know about materials though, Such as, what materials will deteriorate in salt water, and maybe even get eaten by sea life.

I am considering a wrap around that attaches to the upper 1/3rd of the hull by pulling it underneath the boat, stretching a boot around the hull and tying it off to the railings, bulwarks, bowsprits, whatever, so that it is snugged tightly against the upper part of the hull. Then when it inflates, it sticks out along the entire perimeter like a life raft stretched around the hull, or like a life raft with a sailboat stuck in the middle of it. Yes, it will have to be custom made, but won't be too difficult with most hulls I've seen. The flare of the hull itself keeps it from coming off over the top, and it can be tied in place to keep it from falling off.

The beam to length ratio stays the same that way, and the only thing to get in the way is an outboard, maybe a swimming ladder, and maybe the rudder, so maybe there won't be as much lift at the transom. Each boat is different so it HAS to be custom fitted, but I want to minimize the drag and maximize inflation which should be easily accomplished by essentially turning it into an inflated bulwarks.

The problem is that it should be sealed to keep out moisture so that it doesn't trap moisture, or it should only be installed when the boat is going out for a cruise.

[Schoonner]

Originally Posted by portacruise

Very interesting movie clip, that's more than what I thought what sounds like a diesel engine could tolerate on the Jeep. Still, that is only few minute time period in the clip. I wonder how continuous a complete submersion could be tolerated without some problems. Also we don't know if engine problems related to the submersion developed at a later date. There must be a reason IC boat engines are run in dry engine rooms.

P.

Many Many off road vehicles are equipped with this kind of snorkel system. They are mainly used for fresh water and I've never seen anyone get dumb enough to try it at the beach, but painting the engine with different paints will make a huge difference.

The whole thing will come down to whether or not you want your boat to be your life raft, and what you will do to keep as many of your components safe/salvageable when you get back to home port.

[gonzo]

Military vehicles have been using snorkel systems for decades; in salt water too.

[Schoonner]

I wonder if there is a way to make my safety device non-patentable, as I believe that most safety devices should be treated. I want people to expound on my ideas, not feel like I might threaten them with lawyers if they make a safety device that's works out better.

[gonzo]

Patents are voluntary. There is no Law that prevents an inventor from putting his work in the public domain

[ancient kayaker]

Originally Posted by Schoonner

Just to brag a little, I used to be the only one who could take all the wake that the counselor who was head of the boat stuff could muster with a 15ft boat they used for water skiing and still stay upright. He got a little angry and started running the power boat in figure eights pretty close to me trying to get me to capsize . . .

The SOB had no business doing that, just a bully. It's surprisingly difficult to swamp a canoe provided the occupant doesn't panic. If the paddler sits on the floor it will just bob over the waves like a cork. It's usually the paddler panicking that causes the capsize. Of course surf is another matter . . .

[Schoonner]

Originally Posted by ancient kayaker

The SOB had no business doing that, just a bully. It's surprisingly difficult to swamp a canoe provided the occupant doesn't panic. If the paddler sits on the floor it will just bob over the waves like a cork. It's usually the paddler panicking that causes the capsize. Of course surf is another matter . . .

Idk, the waves he was making were coming from two sides, one after the other, and were pretty large. If I let one of them broadside me I'm fairly certain I would have been tossed out of the canoe. I was sitting in the back on the seat provided, and water was getting in over the gunwales, but I used the paddle to make the lightened front end hit the center of the waves he was creating. It was a powerful boat he was using, so the waves he made were probably 4 foot high and stuck up like the pyramids. Every time I let the bow get hit by two at once water came in the canoe and it scared me.