Hull Speed
The theoretical displacement-mode speed limit — determined by waterline length, not engine or sail power.
5.5 kts
A displacement hull pushes a bow wave whose speed is limited by the waterline length.
With a waterline of 17.1′, the X One Design Uk tops out around 5.5 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √17.1′ LWL = 5.5 kts
Performance Ratios
Racing handicap, sail-carrying power, stability and comfort — and what each one actually tells you about a day on the water.
Ballast / Displacement
50.6%
Race-oriented ballast ratio — very stiff and powerful.
Displacement / Length
258
Moderate-heavy — carries provisions well, deliberate in light air.
Hull Speed
5.5kts
Pounds/Inch Immersion
2lbs
Weight needed to sink the hull one inch — loading sensitivity.