Ballast
Also known as: keel weight, stability weight
Weight placed low in a sailing yacht, typically in the keel, to provide stability and prevent capsizing. Modern yachts use lead or iron ballast, often shaped as a fin bulb or in a winged configuration. The ballast ratio (ballast ÷ displacement) is a key indicator of a yacht's stiffness and safety.
Related Terms
Ballast Ratio
The ratio of a yacht's ballast weight to its total displacement, expressed as a percentage. A typical cruising yacht has a ballast ratio of 30-45%, while performance-oriented designs may exceed 50%. Higher ballast ratios generally indicate a stiffer, more stable boat, though hull form and center of gravity also matter significantly.
Technical
Fin Keel
A type of keel that extends vertically downward from the hull with a relatively thin profile. Fin keels offer excellent upwind performance, reduced wetted surface, and better maneuverability compared to full keels or long keels. Most modern production yachts use fin keels, often with a bulb at the tip to lower the center of gravity.
Hull & Keel
Displacement
The weight of the water displaced by a sailing yacht, which equals the yacht's total weight. Measured in tonnes or kilograms. Heavier displacement (diesel, steel, or heavily built) provides more comfort in rough seas and storage capacity but reduces acceleration and top speed compared to lighter displacement designs.
Technical
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