By the time I finish preparing ‘Minnow’ for the water I will
have made changes to most things. Today I devised an arrangement that secures
the kedge anchor in its stowed position, and I fitted a hinge to the cover of
the chain and warp locker. I also made a bracket for securing the lid of the
aft bilge locker. Only two more locker lids require gizmos to stop them from
opening in the unlikely event of a 180 degree capsize. If that dreadful situation were to arise, loose
items on the shelves and in the lazarette would fall out of their compartments,
on account of gravity.
I would rather not think about it, but all heavy items would
stay in place, including the ship’s battery – that’s if I finish the cover for
the box in which it is housed.
‘Minnow’ is designed to self-right. The combination of
buoyancy provided by the coachroof and ballast strapped to the floor, plus the
convex fore and aft decks, will act to right the boat. Wave motion would flip
the boat the right way up. Her short, stout mast and low aspect sail would not
greatly impede the righting action. Her ballast ratio is above average, and her
AVS (Angle of Vanishing Stability – the point at which the upthrust of centre
of buoyancy and the down thrust of the centre of gravity are in line) is way
above average at 160 degrees. Only another 30 degrees of roll would bring her
completely upside down.
Links
Boat Stability
Hull Speed and the Speed/Length Ratio
Understanding the Prismatic Coefficient
Al Law’s ‘Little Jim’ Undergoing Capsizing Load Measurements
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