Ta. Excellent input, as usual.
Heinrich,
I want to eliminate the sea state as a factor, although with a big enough ball and cup, you probably could.
If it capsized quickly enough, the ball would stay on the cup (like whirling a bucket of water round your head). No idea how quick this would have to be.
Paul,
Electric sheet releases scare the hell out of me, but in the right hands (yours, the big tri guys, etc) they would do the job. Also too expensive for me. Do you know of a reliable, cheap version?
JIB,
Much simpler. That will do nicely, thanks. Mk 1 will be just as you have described. Do you want to give it a name?
Robert,
Out of the box, as expected, ;-) but too complex for me. I have often thought about very skinny, deep hulls, but could never get past the wetted surface issues. And the motion is fine, just that with the hull skipping over the waves, a surface following wand might release prematurely.
rob
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