Vintage IOR/One Ton Cup from Newport, Rhode Island back in the 1970s. The
One Ton Cup is a
trophy presented to the winner of a sailing competition created in
1899 by the
Cercle de la voile de Paris (CVP). These
regattas were at the beginning of races between one-tonner sailing yachts,
dinghies, according to the 1892
Godinet rule. This
Coupe internationale du Cercle de la voile de Paris, its original name, has been raced since 1907 on
International 6 Metre, except for four years, from 1920 to 1923, where it was raced on
6.5m SI. In 1965 this one-tonner Cup was thrown in within the scope of ocean racing, on Jean Peytel’s initiative, member of the CVP, following the activity slowdown of the 6m JI class. The One Ton Cup was then raced according to the
RORC rule on 22 feet boats, and on IOR rule on 27.5 feet boats from 1971, followed by IOR rule 30.5 feet in 1984. The
One Ton Cup is a
trophy presented to the winner of a sailing competition created in
1899 by the
Cercle de la voile de Paris (CVP). These
regattas were at the beginning of races between one-tonner sailing yachts,
dinghies, according to the 1892
Godinet rule. This
Coupe internationale du Cercle de la voile de Paris, its original name, has been raced since 1907 on
International 6 Metre, except for four years, from 1920 to 1923, where it was raced on
6.5m SI. In 1965 this one-tonner Cup was thrown in within the scope of ocean racing, on Jean Peytel’s initiative, member of the CVP, following the activity slowdown of the 6m JI class. The One Ton Cup was then raced according to the
RORC rule on 22 feet boats, and on IOR rule on 27.5 feet boats from 1971, followed by IOR rule 30.5 feet in 1984. The IOR concentrated on
hull shape with length, beam,
freeboard and girth measurements, foretriangle,
mast and
boom measurements, and stability with an inclination test. Additionally, the IOR identified features which were dangerous, or it couldn't fairly rate, and penalized or prohibited them. The measurements and penalties were used to compute the handicap number, called an
IOR rating, in feet. The higher the rating, the faster the boat was deemed to be able to sail. A typical IOR 40 footer (a
one tonner) rated 30.55 feet. The IOR rule encouraged wide short boats with limited stability. A narrow waterline and large beam on deck, combined with a high centre of gravity, meant that crew weight provided a significant proportion of stability at small heel angles, and boats had a relatively low angle off vanishing stability. This developed into the situation about 1977 when the boats winning in most smaller IOR categories (up to the half tonners - about 10m LOA) had all internal ballast, often with an unballasted daggerboard. The managers of the rule realised that this was not a suitable direction for seaworthy yachts, and heavily penalised boats with lifting keels. Apart from the girth measurements, all measurements were basically point measurements. This meant that the hull was often locally distorted to maximise or minimise a measurement locally, with minimal effect to the surrounding hull. This gave a characteristic
bumped look to many boats, particularly at the point of maximum beam and in the stern. Also, as stability was only measured at very low heel angles (less than 5 degrees), boats were designed with a very narrow waterline and low stability in measurement trim, but a hull form that gained stability with the weight of the crew and other equipment, and with increasing angles of heel. Interestingly, low stability was encouraged (up to a point) because the initial assumption was that low stability indicated a well fitted out interior, and so more of a cruising boat than a stripped out racer. Secondary design factors included engine and propeller rating factors, minimum internal accommodation levels, safety regulations, and a limit on the number of sails carried on board. Later on, crew limits were introduced, and limits on the use of exotic materials, and also scantlings for hull structural design developed by the American Bureau of Shipping.
