Tank Testing Hull Model International 12 Meter class yacht numbered 6819
Maker
Ben Lexcen
(1936 - 1988)
Date1968
Object number00054981
NameModel
MediumTimber, paint, pencil
DimensionsOverall: 300 × 1444 × 280 mm
Copyright© Ben Lexcen
ClassificationsModels
Credit LineANMM Collection
DescriptionThis is a tank testing hull model for an International 12 Meter class yacht and is numbered 6819. The model comprises a double ended bulb canoe body in white painted timber, scribed with grid lines and with a metal hoop in the interior where a white rope is attached. On the outside, there are several pencil marks in different places.
HistoryTank testing yacht designs has been an important tool for a yacht designer to assess changes in a yacht's proportions and their effects on its potential importance. For many years only smaller scale models could be tested because of the small size tanks available and this is built at 1.13.3 scale to suit the test tank facitity at the University of Sydney.
Ben Lexcen and his design team which included draughtsman and model builder Dennis Philips built and tested a small number of these 1:13.3 scale models for the design of the yacht SOUTHERN CROSS in 1974 with the series number 71xx and 72xx. They were run in the small tank at the University of Sydney Engineering Department.
This particular model has the number 6819 which relates to the series of models made in 1968 during the design of the 1970 challenger GRETEL II. This was designed by naval architect Alan Payne who was also assisted by Dennis Phillips as a draughtsman and model maker. It is built in simlar thicknesses planks to the stock timber they used in 1968 according to Phillips, which helps confirm it is from that period.
It appears to be a situation where this model from 1968 has been modifed by Lexcen and his team with the addition of bulbs to see if this made any difference to the resitence. The idea of bulbs was in vogue in the early 1970s, and the concept was later used unsuccessfully on a full size version of a smaller 6 meter clas yacht, PRINCE ALFRED.
SignificanceTank Testing Builder's Model numbered 6819 has an unorthodox bulb bow and stern configuration. This configuaration was suggested by a small number of designers, based on the success of bulb bows on large ships. This appears to be an adapation added to an existing model because the number 6819 is likley to belong to the series of designs prpeared by Alan Payne for the 1970 GRETEL II challnege. It was built by Dennis Phillips who worked for Payne at that time. There is no evidnece it was used on any final designs by Lexcen, but shows his willingness to experiment and consider unorhodox design ideas.
