on waterline length to discourage the light skimming dishes of the day, displacement was not part of the formula. By contrast the Universal Rule included


displacement in the formula, so that its effect on speed could be accounted for. What Malden did was to combine the best points of both these rules to produce his BRA rule. Shortly after the formation of the BRA


the First World War broke out, and when yachting eventually recommenced after the war the BRA amalgamated with the YRA; although its Eighteen Foot Rule was adopted only three boats were built to it and the International Rule soon became predominant. However, Malden was keen to see how


well his rule worked in practice and whether it equitably rated boats of differ- ent lengths, sail areas and displacements, so he promoted, through his journal, a new rule for model yacht racing which he called the ‘Yachting Monthly Six Metre Rule’ – this later became known as the model ‘A’ Class Rule. This rule has been used from 1926 to


the present day both for domestic and international racing. Pertinently it was used by the Gosport Model Yacht Club which was not far away from the Camper


& Nicholsons Yard and where many of Charles Nicholson’s employees raced A Class boats. Indeed, Charles was a member of the club and it is said that he often used it as his home club when signing the visitors’ book at yacht clubs elsewhere. Anyway, Nicholson took a great interest


in the class and when, after the Second World War, the IYRU perceived the need for a lighter, more modern boat than the Six Metre, and with a smaller crew, Malden Heckstall-Smith and Charles E Nicholson proposed the A Class formula as the basis for this new rule. And so the 5.5 Metre class was born. Interestingly, the same basic formula


was also used for the RORC Rule and later the IOR Rule itself. For those who are interested in such


things, the various rules that led up to the 5.5 Metre Rule are shown below:


RULES Final International Rule (1936…) Rating = L + 2d – F + S0.5 2.37


Where L, d, F and S are all as in the First International Rule. Over the years minor changes were made to various parts of the rule but the essential formula remains the same to this day.


Seawanhaka Rule (1882-1902) Rating in feet = L + S0.5 2


Where L is waterline length in feet and S is sail area in square feet.


Universal Rule (1902-1939) Rating in feet = 0.18*L*S0.5 D0.333


Where L is quarter-beam-length measured in feet at a height of one-tenth of the waterline beam (one-eighth in the J-Class) above the waterline, S is sail area measured in square feet and D is displacement mea- sured in cubic feet.


BRA 18 Foot Rule (1914-1925) Rating in feet = L + S0.5 4


+ L*S0.5 36D0.333 + Penalties = 18ft


Where L is waterline length in feet plus 1.5 times the difference between the girth, covering board to covering board, at the bow waterline ending, and twice the free- board at that point, plus 0.333 times the difference between the girth, covering board to covering board, at the stern waterline ending and twice the freeboard at that point. S is the sail area in square feet and D is the displacement in pounds. 


SEAHORSE 51


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