Some canoes will float well when swamped, some are nuetral- hanging right at the waterline, and some will sink a bit below the waterline. In general, the older aluminum canoe manufacturers built in some flotation in the stems and those canoes floated better when swamped. In contrast my royalex madriver flashback required airbags or the boat would sink a little below the waterline if you swamped it. Even with airbags it was hard to paddle swamped.
I think the smart thing to do is purposefully swamp your boat in a controlled environment and see where you’re at with self rescue. Can you reenter the boat? In some cases I’ve seen flotation impede flipping the boat back over. Coolers and even throwbags can impede this as well. In general, ww kayaks are not made for reentry. Rather you are trying to make the boat easier to corral (plow, bump and chase, toss or tow) into an eddy.
time to bring the max video back
Any flotation below the waterline in or out of the boat adds buoyancy, which plays into how the bag etc is secured.
Ok , this might sound dumb , but I assume we are only talking about really cheap or really old entry level Kayaks where they do not have sealed bulkheads? I kinda of skipped the big box kayaks and went to the next level with sealed bulkheads front and rear.
In fact it is only the flotation volume below the water line that does anything. The rest of that volume/height of the boat is there to keep water from coming over and filling the volume that is doing the job. That’s why you can have scupper holes that let water out if the boat is sealed below the water line.
Air or float bags is the same.
in general sealed bulkheads replace the need for added flotation but the only way to know for sure is to purposefully swamp your boat and to see if you can reenter it and paddle it swamped. Sometimes hatches and bulkhead seals aren’t water tight. I used to carry a sponge in the hatch of my LLxp for a reason.
I think of air bags in terms of taking up space and displacing water. If the boat is crammed full of air there ain’t no room for the water to fill it up.
Correct. In my case and the one shown in the OP had a sealed compartment in the stern but only a foam block in the bow. I felt filling that fuller was an improvement.
Putting a flotation bag inside a sealed compartment will do nothing unless your bulkhead/hatch leaked.
Right… and it makes you ride higher. Unless the bags etc are secured very loosely and/or partially inflated.
If you have bags well inflated, and tightly strapped with just room for yourself, you will be riding higher. Which can be good or bad… just something to be aware of.
This is true once you take on water. In a dry boat there is no change.
If you take on water and the float bag isn’t secured to the bottom it will just float up and do nothing.
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Unless they are foam packed, I just assume the tanks leak. That’s been my experience with canoe tanks… I think they are silly, and over time actually start trapping sediment, moisture etc ie weight.
I just ordered a new canoe and had them delete the tanks. More space for bags.
That isn’t what you said in post 5 though or at least i misread what you were saying.
There is another distinction between yoga ball and any kind of rubber flotation device and ridged devices made from vinyl or rubberized cloth materials and that is they stretch and deform. Think of it like a regular balloon and a Mylar balloon. When the Mylar balloon starts to lose pressure it gets saggy instantly, a rubber balloon will still look the same just smaller.
This is maybe why I don’t see the change as much with mine hot to cool days I have inflated them to a point where when they cool they still hold shape. 
Your video is funny and it would be funny if it weren’t so true. This guy and his buddies are what gives the whole rec-kayak image a bad name. I can go out on any weekend on our river here and see a dozen of these guys just waiting to make that video. They show him perfect along with his girlfriend. No PFD and as he is going down he finds it and puts it on but without buckling it. There is one redeeming safety feature to the video and that is she is smart enough to keep her distance and make a movie as in getting any closer he will have her in the water with him.
It does look like the one hatch compartment is working to save the boat.
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Flotation inside a dry hull does not add buoyancy. It is the hull that displaces water and it is the displaced water that creates buoyancy. Only if the flotation increased the volume of the hull would it add buoyancy.
In fact, adding flotation to a dry canoe or kayak will result in the hull riding slightly lower in the water as a result of the weight of the flotation itself and whatever device(s) are used to restrain it.
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Swamping your boat or at least flipping it upside down and then righting it to see how much water remains is a great idea everyone should try.
In the case of my canoe my air bags are round cylinders that fit the hull on the bottom pretty well and the cylinders extend slightly above the gunwales so the strapping against the tops keep them planted firmly down. When my canoe is upside down sitting in the water it is virtually empty of water. It is in flipping it back upright it picks up some water by way of scooping and the faster it is flipped the less water that gets in. A line run from the far side and over the bow with it upside down that can be pulled from the water is pretty fast.
I have contemplated putting sponsons on to keep the scooping down and it could even be on the inside of the canoe up by the gunwale I think. I’m surprised at how few rec-canoes don’t have sponsons and how few aftermarket selections there are out there.
I also normally carry a cooler that is light weight and would float that fits side to side and is the same height as the canoe is deep. I secure it in and I have the lid secured to stay shut. I have lunch in there on ice and some water and maybe fish I have caught but it is mostly air and I don’t trust the top seal to be water tight. That cooler space is a lot of flotation potential also. I have been looking around for a new one with a lid that seals tight.
Yes yes of course you guys are right… easily illustrated by putting a small bowl in a larger and pressing into water… the small bowl does not float until water comes over side of larger. And buoyant objects don’t float in a dry canoe.
Too much coffee, or maybe too little…
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well if the cooler spills just remember beer floats (only slightly) and pop sinks. I snagged a high end mexican import on the pagosa springs town run, arkansas river. Actually I think I was on the san Juan that day. Beer was probably lost by a tuber. I believe in bein’ international- wvirginian drinking mexican beer in colorado on a river named for Puerto Rico City, I’m assuming the can floated away from a texan (majority of tourists in Co) consumed at a take out called yamaguchi park. Can’t make that stuff up- of course you can be patriotic but I’m not sure red, white and blue is made anymore, might have to settle for a pbr- the can is red white and blue.
My daughter tells me I’m a free-a-tarian. If it’s free I’'ll eat or drink it.
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bud I like your name, buy a new cooler or a roll of duct tape and a knife, a popular overnight option for sealing coolers, especially for multiple day use.
pblanc I know some rivers where the hull displaces the water and puts it right into the bow of the canoe. I figure you know about those places as well. If canoes aren’t decked or skirted, then the air bag can actually deflect the water away from entering ithe boat. kinda important when running drops and such.
Side air bags that sit inside the canoe hull adjacent to the paddler(s) seem to be more popular in Britain than in the US for some reason.
It is not uncommon for whitewater open boaters to glue minicell panels into the sides of their boats in the cockpit area to displace water. This not only makes reentry easier, it makes rolling the canoe easier since the hull scoops less water as it comes up. Only a few gallons of water add a lot of weight that resists the hull rotation to an upright position.
Ray Goodwin is a pretty well-respected British canoeist who has written pretty extensively on a variety of topics including swiftwater rescue and recovery. He has worked out a system for unassisted deep water canoe reentry that is somewhat innovative and incorporates side air bags. It is rather slow and has a lot of moving parts, but it works for him.
interesting system he has developed. Using water in a bag as a counter weight a nifty idea.
I enjoyed the beer story. I bought a new car once and my father in law said “My God I didn’t think new was in your vocabulary”. The house we live in now is in a quaint little town that French Creek runs thru and I found a house for sale that had been abandoned for several years and needed a lot of work got it for $24k and the total taxes are $350 a year. Took a year buying every item to rebuild the place except drywall off of Craigslist or other person to person. Free is best but cheap is good too and tax free is really good. We have nice place now no payments and canoeing out my back door. Oh did forget retired also.
Your daughters name for you made me laugh. When my son was in high school he would be going someplace with me in my old truck and I would see a pile of stuff piled at the curb and start to slow down to take a look and he would yell at me that he knows the girl that lives there and doesn’t want to commit social suicide with his dad picking thru her junk. I said but that push mower looks so nice and he said ya like the 10 you have already.
Good to know beer floats here I thought only light beer floated. I will think on the duct tape solution and keep my eye open for free floating beer.
