5.5 Metre
international racing sailing class
The International 5.5 Metre class was created to yield a racing keel boat that would give a sailing experience similar to that of the International 6 Metre Class but at a lower cost.
The main class regulation restricts a single quantity output from a formula involving the boat's rating length L, weight (expressed as a displacement D) and sail area S; the regulation states that the output of this formula must not exceed 5.500 metres. There is considerable scope for variations in design while still meeting this restriction, and as a result, each 5.5 metre boat is unique.
If the design parameters of a proposed new boat result in a formula output exceeding 5.5 metres, then one or more of the parameters must be suitably adjusted. Performance data gained from testing models towed in a long water tank (referred to in yacht design as a Ship model basin) can suggest optimal combinations of parameters.
The 5.5. metre rule is a variant of the International Rule (sailing) established in 1907. The 5.5. is therefore closely related to larger metre boats such as the 6mR, 8mR and the 12mR.
Since 2010, the 5.5 Metre is one of the Vintage Yachting Classes at the Vintage Yachting Games.
History
The 5.5-metre class was a redesign of the 6-metre class by Charles E. Nicholson in 1937.
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This entry incorporates text from “5.5 Metre” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.