Unexpected result in swamped boat

Just finished my changes on my LL Stinger XP. Added rear bulkhead to make entire rear end water tight, installed front NRS flotation bag and sheet of 2" closed cell foam to foot board on back side to further fill up front cavity.

To test rear bulkhead I filled it with water and had no leaks after 2 hrs sitting full.

I took it out on a calm section of river to see how it rolled and check for fitting, being the idiot that I am I rolled and forgot I had my paddle stuck in the front loop of my skirt, so I popped my skirt while upside down, finished the roll with a swamped boat.

I was pleasantly surprised that high rocker made the weighted center made the boat crazy stable, totally unlike my touring boats. This has just become my boat to help people practice wet re-entry. I realize waves will make the equation different, but I am blown away with the result of my non-scientific test.

Is this possible with other high rocker boats? My Zephyr and Avocet have some rocker but when they get swamped they are completely different animals.

Swamped Blue Hole canoe was similar
I had a Blue Hole for a while. I had air bags, but there was still significant volume that could fill with water. The issues were that it was very slow, required a lot of clearance over rocks and it’s generally cold water you are sitting in. But it was pretty stable.

There is some way that rocker in ww
designs makes for stability. My MR Synergy is rather roundish in cross section, and rather narrow (30"), but it firms up very quickly as it tips.



But other features of a design can overcome rocker, and overcome flatness. I have a 1982 Kevlar Noah Magma, with good rocker for the time, and a distinctly flattish cross section. I always cite it as a counterexample when some insist that flatness always makes for stability, because the Magma has rather low primary and secondary stability. I think one reason it came out that way is that designer Vladimir Vanha had “grown up” with roundish kayaks, with low stability. So the Magma seemed just fine to him. I watched him slalom racing in it, and he just loved to edge the boat on its sharp chines.

Seen this before
in an Arluk III. The boat has a bow and stern both slightly higher than the deck. You can do this with sufficient rocker as well so that the boat never really capsizes. The Arluk, when capsized, just lays on its side and the paddler can recover without ever being inverted. A decent brace or forward stroke is all that is needed.



All this, of course, requires both the bulkheads to be waterproof. An image of the Arluk:



http://tinyurl.com/ld7tbqh





Rick