Wednesday, January 15, 2014

Fixing ‘Minnow’

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.


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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