Scale: 1:6. A total of three tank-testing models for this trimaran yacht were acquired (one depicting each of the hulls), along with a full hull exhibition model (SLR0302), from the same source. Tank test models are, literally, tested in a tank of water to measure and evaluate the efficiency with which a hull behaves as it travels through water. Even today, with computer-aided design technology, models continue to be used in this way. The example here is typical in that it has been made from laminated softwood, the centre hollowed out, and the outer profile sculpted, until the optimum hull form has been achieved.

The 'Triune 30' (1966) was designed by P. R. (Robin) Chaworth-Musters, and built by his company, Musters Marine Ltd, in Poole, on the south coast of England. It had a glass fibre hull, deck and coach roof, and was cutter-rigged on an alloy mast and main boom. It was aimed at an increasingly affluent and pleasure-seeking market and, in looks at least, was a complete departure from the traditional cruising motor yacht.