5.5 Metre (keelboat)

The International 5.5 Metre Class was conceived as a type of racing keel boat which gave a similar sailing experience to the International 6 Metre Class but at a lower cost.

Each 5.5 metre boat is unique because considerable variation is allowed by use of a design formula. The various design parameters of a new boat (eg, length, weight, sail area etc etc) are input into the 5.5 metre formula and the result must be 5.5 metres. If the result is not 5.5 then a parameter or combination of parameters must be adjusted to achieve a result of 5.5 metres. The best combination of parameters is supported by performance data gained from testing towed models in a long water tank (referred to in yacht design as 'tank testing').

The first boats conforming to the 5.5 metre rule were built in 1949

The 5.5 metre design was very successful and replaced the International 6 Metre as a class sailed in the Olympic Games

External links

• Official International 5.5 Metre Class website