30.5 IOR Sloop, Deck Cambers
Designer
Ben Lexcen
(1936 - 1988)
DateMay 1984
Object numberANMS1543[025]
NamePlan
Mediumdrafting film
Copyright© Ben Lexcen
ClassificationsMaps, charts and plans
Credit LineAustralian National Maritime Museum Collection
DescriptionThe ‘deck camber’ and construction drawing for a 40-foot ‘One Ton’ IOR yacht, designed by the Ben Lexcen Design office 1984.
HistoryThe International Offshore Racing (IOR) system functioned from the 1960’s up to the early 1990’s when the International Measurement System (IMS) was brought in. During its use, it concentrated on the shape of the hull, along with length, beam, the freeboard and girth measurements. It also measured the fore-triangle (sails), the mast, boom, and the yachts stability. The stability was carried out with an inclination test. These measurements 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. The IOR ‘One Ton Cup’ series enjoyed a renaissance in 1984, following the decision of the Offshore Racing Council in 1983 to increase the One Ton rating from 27.5 to 30.5-feet. This 30.5-foot ‘One Tonner’ by the Ben Lexcen Design office, is APOLLO IV designed for Alan Bond and built in 1984. With an overall length of 12.20 meters (40-feet) it was built of carbon fibre composite in order to reduce the overall weight while maintaining sufficient strength for the rigors of offshore racing. APOLLO VI was designed and built in 1984. She was launched in November of that year, and took part in trials races, held off Sandringham, for the 1985 Admirals Cup. ‘APOLLO IV’ came 4th. in the trials so did not qualify for the Australian Team. She then became a development yacht for Alan Bond, and underwent several design changes, including a new deck layout. APOLLO VI was bought by Paul Stuart in 2006 who raced the yacht successfully for many years, including the Melbourne to Osaka race in 2018. The yacht was still sailing in 2023 but believed to no longer race.SignificanceThe Ben Lexcen Design office, which included the talented naval architect Peter Lowe, designed this 30.55 IOR measured yacht in 1984, the year the IOR rules and measurements were changed. Previously 27.5-feet, the new measurement resulted in an a typical IOR 40-foot yacht (a one tonner) rated at 30.55 feet.
