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Lead line plan for model 6819/1
Lead line plan for model 6819/1

Lead line plan for model 6819/1

Designer (1936 - 1988)
Datec 1970
Object numberANMS1543[037]
NamePlan
MediumPencil on drafting film
Dimensions610 x 770
Copyright© Ben Lexcen
ClassificationsMaps, charts and plans
Credit LineAustralian National Maritime Museum Collection purchased with USA Bicentennial Gift funds
DescriptionBen Lexcen (formally Bob Miller) ballast keel lines-plan and weight calculation, for a proposed lead ballast keel on the 12mR America Cup challenge yacht SOUTHEN CROSS designed and built in 1974. History"A self-taught naval architect, yacht designer and accomplished yachtsman, Ben Lexcen was born Robert Clyde Miller, on March 19th. 1936 at Boggabri, a small town in New South Wales, Australia. His early years were tough, being abandoned by his parents, he grew up with his grandfather in Newcastle. He left school at fourteen, after only five years formal education, to become an apprentice machinist at the New South Wales locomotive works. In 1952, at the age of 16, he designed his first sailing boat THE COMET with his friend William Bennett and soon began to make a name for himself at local sailing competitions. In 1960 he entered his boat TAIPAN in the 18-Footer World Championships, and later winning the World Championship in 1961 with his next boat VENOM. In 1962, together with his friend Craig Whitworth, he set up a sail making business in Sydney while continuing to design boats and small yachts. He represented Australia in the Soling class at the 1972 at the Olympic Games at Munich, West Germany. Ben Lexcen, (aka. Bob Miller) quickly became known for his fast, light-weight, racing yachts which included, PLUM CRAZY, MERCEDES III, APOLLO, APOLLO II GINKGO, BALLYHOO and CEIL III. These early yacht designs were not tank tested as the process is costly and time consuming. It requires a number of different hull models to be designed, built, and tested in a purpose-built water tank facility. The costs involved would have been too high, and considered unnecessary, for owners of yachts of around 45-feet long. Alan Bond and Bob Miller (later Ben Lexcen) were together at Newport, Rhode Island in 1970 for the Newport to Bermuda race. Together with the Australin team, they were preparing Alan Bond’s racing yacht APOLLO, at ‘Bob Direcktor’s Shipyard, at Mamaroneck, Yew York. While visiting a boatyard together at City Island, New York, Alan Bond spotted a large sailing yacht alongside, which unusually, had all the deck winches and crew positioned below deck. Alan Bond wanted a closer look so wondered down the pontoon to study the boat and layout but one of the crew took offence and shouted for him to go away. This did not go well, and when asked what type of boat it was anyway, was told it was the America Cup yacht ‘VALIANT’. Still mystified, Bob Miller explained what the America Cup was and about the yachts involved. To which Alan Bond told Bob Miller. ‘You design me one of those 12-metre boats, and we’ll come back here and win their bloody America’s Cup.’ In 1973, during the design and development of the 12mR yacht SOUTHERN CROSS (K-4) for Alan Bond and the Australian America Cup challenge team, several hull designs were proposed, and scale models of them built. The yacht represented Australia, design, build, management and above all, the nation’s sailing skills and ability. The defending American design team had a large budget, the best materials and resources to draw on, so carried out extensive design work and tank testing. Several scaled models of SOUTHERN CROSS hull and ballast keel were built, varying from 1.41 metre to 1.51 metre in length overall. When tank testing, an allowance is made for the actual weight, so they can be tested in the water to check the designed hydrostatics, pounds per inch of emission, hull resistance, wave making, overall displacement and so forth. These tests take place in large, purpose-built water tanks, which allows the vessel to be towed though the water and information gathered to fully optimise the hull shape. With a final overall length of 20.45 metres (67.09 feet) and beam of 3.71 metre (12.17 feet), SOUTHERN CROSS (KA-4) was built of aluminium at Terry Hills, Sydney by ‘Halvorsen Morson and Gowland’ of Mona Vale and launched in 1974. Following sea trials and crew training alongside the previous challenge yacht GRETEL II, SOUTHERN CROSS was shipped to the USA for the American elimination trials. The American 12mR yachts; ‘INTREPID’, MARINER’, VALIANT’ and COURAGEOUS’ were all trying to be the defending yacht for the cup challenge. Skippered by talented Australian Jim Hardy, SOUTHERN CROSS did her best but ultimately lost to ‘COURAGEOUS’. SOUTHERN CROSS was not successful in winning the America Cup in 1974 but in 1983 Alan bond returned to Newport with the Ben Lexcen designed AUSTRALIA II. Captained by John Bertrand, the yacht beat the American yacht LIBERTY and Australia finally won the America’s Cup. SignificanceThe lines-plan for a proposed lead ballast keel made by Ben Lexcen during early development work on Alan Bond’s first 12mR yacht ‘SOUTHERN CROSS in 1973/74. The work shows the ballast keel with a curved trailing edge, similar in profile to that made on the wooden 57-foot APOLLO, designed by Ben Lexcen in 1969. The plan view of the five waterlines of the keel shows a sharp leading edge, later improved when the designer used NACA airfoil sections, which provide more lift and less drag. It represents the start of Alan Bond and Ben Lexcen’s quest for the coveted Americas Cup, when advanced designed, purpose built 12-metre yachts, raced against each other. Although SOUTHERN CROSS did not win the 1974 America Cup Challenge it did pave the way for Ben Lexcen and Alan Bond to build a close relationship which would eventually come to fruition in 1983. Captained by John Bertrand, ‘AUSTRALIA II,’ the revolutionary yacht with the famous wing keel, won the Americas Cup race, and the famous trophy finally came to Australia.