Catamaran Hull Speed Calculator
The catamaran hull speed calculator estimates the theoretical maximum cruising speed of a multihull vessel. Unlike monohulls, which are limited by the standard 1.34 constant, catamarans utilize slender hulls to "punch through" wave resistance, allowing for significantly higher speed potentials.
Why Catamarans are Faster
In naval architecture, monohulls are governed by the "Square Root of LWL" rule. As they approach the speed of the wave they create, resistance increases exponentially. Catamarans bypass this "speed wall" because their hulls are extremely slender.
The "Hull Constant" Explained
- Cruising Cat (1.55): Designed for heavy payloads (water tanks, generators, dinghies). They sit deeper and have more wetted surface area, creating more drag.
- Performance Cat (1.75): Optimized hull shapes, often featuring wave-piercing bows and reduced wetted surface. These boats comfortably exceed monohull speeds.
- Racing Cat (2.10+): Ultralight construction, daggerboards, and minimal interior weight. These are capable of true high-speed performance where the hull may even lift partially out of the water.
A Note on Real-World Performance
These numbers represent theoretical capability. Real-world speed is heavily dependent on sail area, wind angle, sea state, and boat weight. A catamaran heavily loaded for a multi-year blue-water cruise will perform closer to the "Cruising" metric, regardless of its original design.