Sailed an O'Day 21 time after time in roaring winds with a friend off the coast of Guam, trying to lay it over to see where that point of no return was, but as US27inKS was saying about how the boat rounding up, this boat would do the same. It "seemed" impossible to dunk, until...
We went out one day and brought my friend's brother and sister-in-law. Same scenario, windy day, fun day, until...
Saw a squall coming across the water. Did NOT have sheet in hand, but then, why worry, it'll go over and head up into the wind an pop right up as usual, right? Nope, not this time. As the winds hit I regretted the fact the sheet lay at my feet. I couldn't get to it quick enough to spill wind and we went over.
The added weight of the two additional bodies caused the rail to dip significantly enough so as to create drag on the down side and combined with the winds blowing us sideways we did not come up into it as "usual". We went over. Winds and swell continued to push on the hull until it turtled. Everything in the boat began to either sink or float away with the wind and swell.
45 minutes later, after bending the centerboard with our weight trying to right the thing, and only after "lowering" the sail, which meant bringing it up from where it hung on the inverted mast, did we manage to right the thing.
It took another half hour in blustering winds and choppy seas to go from a boat fully awash (thank God for positive flotation) before we began to make headway with our bailing efforts, due only to the fact we managed to salvage the cooler before it floated out of reach. It was our bailing bucket.
Oh, did I mention the two additions could not swim and, though wearing May Wests, were a liability due to the fact that, as they reached up to hang on to the boat, their vests would ride up over their heads, so as we attempted to right the boat they couldn't (wouldn't) let go long enough to allow us to do so.(I subsequently affixed crotch straps on all May West-type vests)
Needless to say, don't take ANYTHING for granted and ALWAYS keep that sheet line handy.
I've had tillers break (Tahiti Ketch off Cal coast), rudders break & rigging break (cats & mono), broached to a point of half the boom and skylight in water (36' Choi Lee, running, with 30ft following seas, gale winds), taken knockdowns (see above

), had rails as well as lifelines awash, but nothing scared me as much as when two people could have lose their lives because of my inattention to details (sheet line not in hand).
But event this is to be considered a "POSITIVE" experience. I learned something that day that has carried through some 35 more years of sailing (and counting).
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