Sketch of keel plan for AUSTRALIA II
Designer
Ben Lexcen
(1936 - 1988)
Date1980 - 1983
Object numberANMS1543[364]
NamePlan
MediumCopy of film
DimensionsOverall: 650 x 340
Copyright© Ben Lexcen
ClassificationsMaps, charts and plans
Credit LineAustralian National Maritime Museum Collection purchased with USA Bicentennial Gift funds
DescriptionA Ben Lexcen pencil drawing from 1981, with hand written notes and calculations, for the revolutionary inverted winged ballast keel on the Australian challenge yacht AUSTRALIA II.
The drawing indicates Lexcen's use of the traditional method of drawing, measuring and mathematically calculating the volumes, areas, weights and centres. This work is now, almost universally carried out using computer aided drawing programs (CAD). HistoryAustralia’s quest for the coveted Americas Cup began in 1962 with the Alan Payne designed GRETEL. This was followed in 1966 with the Warwick Hood yacht DAME PATTIE and by GRETEL II in 1970. In 1973/74 entrepreneur Alan Bond, hired Ben Lexcen, (then Bob Miller) to design the 12 metre challenge yacht SOUTHERN CROSS (KA-4). Based on a lifelong experience designing, building and racing, fast sailing yachts, Lexcen, was the obvious choice for Bond. A successful small boat designer and international Olympic sailor, Lexcen had designed many successful ocean racing yachts including: PLUM CRAZY, MERCEDES III, APOLLO, APOLLO II, GINKGO, BALLYHOO and CEIL II. The 1974 Australian challenge was not successful, but he went on to design and build AUSTRALIA (KA-5) for the 1977 and 1980 races.
For the design of AUSTRALIA in 1977, Lexcen teamed up Johan Valentijn, an experienced Dutch naval architect, who had previously worked for ‘Sparkman & Stephens’ in the US. The designers worked together on a number of yachts, including the 45-foot IOR yacht GUIA V in 1976, for the experienced Italian ocean-racing yachtsman, Giorgio Falck. Lexcen and Valentijn spent seven months in 1976 testing 1/9th scale models of AUSTRALIA (KA-5) at the University of Delft test tank in the Netherlands. This period of on-site design and tank-testing scaled models in the water, proved vital for future design work on AUSTRALIA II (KA-6). With considerable experience in tank testing 12 metre racing yachts, using the Netherlands Ship Model Basin in Wageningen was an obvious choice for Lexcen. Many design drawings were produced, and scaled models built and tested. A computer analysis was made at each design change, using tank testing software and collaboration with the ‘National Aerospace Laboratories of the Netherlands’ (NLR).
SignificanceIn an age of computer aided design drawings, when areas, weights, and other calculations, are made in a moment, the hand drawn design work and calculations made by Lexcen in 1981 is a remarkable insight into a ‘living working drawing’. During the four months he spent at the ‘Netherlands Ship Model Basin’ test facility, numerous design drawings and test models were produced and many changes made to both the hull and ballast keel of AUSTRALIA II. It was a period of ‘on-going’ design ideas, changes and improvements, at the tank testing facility. Lexcen’s ideas, notes and calculations at the time are clearly visible on this inspiring work. 
