Although some may say that it is not a design flaw, I would not personally want to sail a boat that had it's keel attached in such a manner. I would rather go a bit slower and be safer.
Ex-Cal - although it may have come off from lateral forces, rather than the inititial hit, you can't say that all fin keels would have immediately suffered the same fate. I am not an engineer
, but common sense would say that if that keel was attached over an area twice as long, and perhaps 4 times as wide (like fin keelers who's hulls sweep down into the keel as opposed to flat bottom boats with a narrow keel bolted on), the keel certainly would have been on long enough to put out a kedge or have it towed off. The long keel would have applied more force to the attachment point as well, even laterally.
To me, if it's going to be deeper, it has to be attached over a greater length and width.
I had a 23' mid - long fin (encapuslated) keeled boat, with a wider attachment point few years ago. It broke it's mooring
line in about 4' chop on a large lake. It blew into a sandy cove where it laid on it's side for an hour or so, until the keel beat an area of sand away underneath it, and it floated upright. (in about 2 ft of water)
Conditions were too bad to try towing it out, so it sat there for another day, until we walked out to it, ran a line from a halyard
to heel the boat, and easily pushed it back into deep water
The only damage was the paint
removed from the bottom of the keel.
There is a definite tradeoff with different designs. I think deep, thin keels are Ok for racers (or others who know it's limits), but I would not want to be cruising on one with my family
This captain should not have run aground, but sooner or later, we all do, and I want a boat that will hold up as well as possible. This one did not!!
I have ran into a sand bar with my current
30'er (same buiilder / design as my old 23'er) at 5 kts or so. The nose dove down from the impact, and we stayed for the nbight on the sandbar, listing slightly. It was on a river, so there were no big waves pounding at us (1 - 2 ft maybe).
Next morning we freed ourselves, after a couple of hours (we were really stuck at we had tried motoring free the night before, and only dug the keel in further).
No damage! Not that this is the "best" design by any means, but don't tell me this keel will fall off as fast as the J-boat!